(all times BST) Welcome to Middle East Live.

As clashes in Damascus continue, there is much diplomatic jostling ahead of a UN security council vote on Syria.

Here's a roundup of the main developments:

Syria

• Rebels said they shot down an army helicopter over the Syrian capital as one of their commanders confirmed that a battle to liberate Damascus had started, Reuters reports. Colonel Qassim Saadeddine, spokesman of the joint command of the Free Syrian Army inside Syria, said: "The Damascus battle has priority for us." He confirmed that the battle had been dubbed the "Damascus volcano". But other activists said the battle for the city had not begun. Abu Raed, a coordinator in Qaboun for the Free Syrian Army, the coalition of rebel fighters, told the New York Times: "It is more ebb and flow; these skirmishes are just a test as our fighters infiltrate then withdraw."

• The state news agency Sana continues to portray the rebels as terrorists, blaming them for a number of attacks in and around Damascus, including using residents as human shields. It said government forces inflicted "heavy losses in the terrorists' ranks".

• The UN security council is expected to vote later today on a UK drafted resolution that threatens Syria with sanctions in 10 days unless the Assad regime complies with a peace plan. Russia and China are expected to block proposals as they tie continuing the UN's monitoring mission with chapter 7 of UN's charter, Bloomberg reports.

• But Russia has submitted its own, "enhanced," draft resolution after president Vladimir Putin met Kofi Annan in Moscow yesterday, RIA Novosti reports. Alexander Pankin, Russia's deputy ambassador to the UN said. "We have taken into account [in the enhanced draft] concerns over humanitarian situation, human rights and localized ceasefire. This idea has been discussed by Kofi Annan with the Syrian leadership in Damascus. It seems to be rather effective."

• Manaf Tlass, a former Republican Guard who defected earlier this month, has signalled that he is willing to lead a transition government. He issued a statement to the French Press Agency in which he said:

I sincerely hope that the blood stops flowing and that the country emerges from the crisis through a phase of constructive transition that guarantees Syria its unity, stability and security, as well as the aspirations of its people. I am ready like any other Syrian, with no other ambition, to fulfil my civic duty to contribute to a better future for my country, as much as I can, and like all those … who have already made many sacrifices.

• Final election results have confirmed that the centrist National Forces Alliance, led by Mahmoud Jibril, has a commanding position in the new parliament, winning more than double the seats of its principle rival, the Muslim Brotherhood's Justice and Construction party. More conservative Islamist parties fared even worse, with the al-Wattan party of Abdul Hakim Belhaj, a former Islamic fighter who is suing former foreign secretary Jack Straw for alleged complicity in his rendition by the CIA in 2004, failing to win a single party seat.

• A key court decision on the dissolution of parliament and a constitutional power grab by the military council has been delayed until Thursday, the Egypt Independent reports. The court has been hearing cases against the constituent assembly, the Shura council, the supplement to the constitutional declaration, and President Mohamed Morsi's decree to reinstate the People's Assembly.

Syria: The Dutch journalist Sander van Hoorn reports heavy fighting in the northern Damascus suburb of Qaboon.

Driving close to Kabun, north #Damascus. Heavy fighting. Hundreds of ppl leaving their homes. #Syria — Sander van Hoorn (@svhoorn) July 18, 2012

Qaboon saw some of the worst violence yesterday. The activist group, the Syrian Revolution General Commission, said government forces began shelling the area and attacking it with helicopters after sealing it off.

Meanwhile, video has emerged purporting to show shell damage to buildings in the southern suburb of Midan.

Syria: Two more brigadier generals have fled to Turkey, AFP reports citing a Turkish foreign ministry official.

"Some 330 Syrians including two brigadier generals fled to Turkey Tuesday night," the official said.

On Monday night a brigadier general and several other military officers were among 1,280 Syrians who crossed the border, according to the Turkish daily Zaman.

Syria: More than 50 members of the regular army, including two colonels have been killed in fighting in the Damascus over the last two days, according to the British-based Syrian Observatory for Human Rights.

The Observatory's Rami Abdulrahman told the Guardian that the information was based on conversations with three doctors from two military hospitals in Damascus.

"The news is confirmed today by three doctors," he said.

One injured officer questioned why the Syrian media had stopped releasing information about military deaths, one of the doctors said, according to Abdulrahman.

Around 12 rebels were killed yesterday, Abdulrahman claimed, including three in Douma and seven in Qaboon.

He claimed deaths among regular troops outnumbered rebel casualties because of the hit and run tactics used by rebels. He said rebels had used RPGs to attack army vehicles carrying many troops, and then went into hiding.

Update:

The Dutch journalist Sander van Hoorn provides partial corroboration about military deaths after visiting one military hospital in Damascus.

Also visited military hospital. They had 34 soldiers there that died yesterday. Hospital (1200 beds) operating at full capacity #Syria — Sander van Hoorn (@svhoorn) July 18, 2012

Syria: A French investigation has concluded that Gilles Jacquier – the first journalist to die in the Syrian conflict – was killed by opposition fire, Le Figaro reports (in French).

Jacquier was killed along with eight Syrians during a government-organised visit to Homs last January.

Le Figaro quotes an unnamed defence ministry source as saying: "Ballistic analysis and information gathered on site by our sources just after the incident indicate that Jacquier was killed by 81mm mortar shellfire coming from a Sunni rebel neighbourhood ... Analyses show quite accurately the source of the shot."

It adds that according to the source "all specialised services (DGSE and DCRI particular, NDLR) are in agreement on this conclusion".

Syria: Reuters is reporting another suicide bombing in Damascus, citing state TV.

FLASH: Suicide bombing at national security building in Damascus - Syrian state television — Reuters India (@ReutersIndia) July 18, 2012

Syria: The journalist Zaid Benjamin, who claims to have been the first to report the start of the rebels' "operation volcano" assault, now says the Free Syrian Army is discussing withdrawing from Damascus.

The Free Syrian Army is discussing to halt #Damascus operations "Logistics supply lines are too long and out weapon capacity is limited" — Zaid Benjamin (@zaidbenjamin) July 18, 2012

Syria: Latest on the reported bombing in Damascus:

Damascus security building was targeted during a meeting for ministers and security leaders: state TV #Syria #Breaking — Al Arabiya English (@AlArabiya_Eng) July 18, 2012

Free Syrian army sources announce that Syrian Ministry of Defense has been killed #Damascus #Syria — Moh'd Yousef (@JawazSafar) July 18, 2012

Note: Other tweets suggest the defence minister may have been injured.

Lots of confused noise about this attack on the security building in Damascus #Syria — Maysaloon (@Maysaloon) July 18, 2012

Syria: State TV has confirmed that some of those attending the ministerial meeting were critically hurt in today's bomb attack.

Meanwhile, an activist in the area claims Republican guard troops have sealed off the Shami hospital in Damascus suggesting that high level casualties could have been taken there.

Republican guards now around Shame Hospital #Syria #Damascus — Majd Arar (@MajdArar) July 18, 2012

Surely many officials now in Shame Hospital, even now and then shaded cars arrive #Syria #Damascus — Majd Arar (@MajdArar) July 18, 2012

Young boys, seems to be relatives to those targeted today in #Rawdah are entering Shame Hospital, their grieve is evident #Syria #Damascus — Majd Arar (@MajdArar) July 18, 2012

Doctors are brought now in shaded 4WD cars, guarded with military police. #Syria #Damascus — Majd Arar (@MajdArar) July 18, 2012

Something big happened in #Rawdah, I can see lots of security & civilian cars in Shame Hospital, roads are closed now. #Syria #Damascus — Majd Arar (@MajdArar) July 18, 2012

Syria: State media has confirmed that the defence minister was killed in the blast, according to multiple sources:

#SYRIA TV CONFIRMS MOD DAOUD ABDALLAH RAJHA DIED IN THE BLAST — Shakeeb Al-Jabri (@LeShaque) July 18, 2012

BREAKING: Defence minister has been killed - State TV. #Syria — Sami al-Hamwi (@HamaEcho) July 18, 2012

SYRIAN DEFENCE MINISTER CONFIRMED KILLED IN DAMASCUS BLAST. MORE SOON... — Al Jazeera English (@AJEnglish) July 18, 2012

Syria: The defence minister, Gen Dawoud Rajha, was a Greek Orthodox Christian from Damascus. Aged 65, he was appointed defence minister last August. He had previously served as the army's chief of staff.

He was reportedly present at another high-level meeting in May where the rebel sources claimed to have poisoned several of those attending.

A Reuters article earlier today described him as one of Assad's inner circle:

Assad has taken charge of a military crisis unit and takes all the daily decisions, from the deployment of army units to tasks assigned to the security services, as well as mobilisation of the Alawite Shabbiha, the feared militia accused of a series of massacres in the past two months. "Bashar remains the centre. He is involved in the day-to-day details of managing the crisis," said a Lebanese politician close to the Syrian rulers. "He set up an elite unit led by him to manage the crisis daily." In this unit, intelligence chief Hisham Bekhtyar is responsible for security coordination, Dawoud Rajha is minister of defence, Assef Shawkat, the president's powerful brother-in-law, is deputy chief of staff of the armed forces. Alongside them are Ali Mamlouk, special adviser on security, Abdel-Fattah Qudsiyeh, head of military intelligence, and Mohammad Nassif Kheyrbek, a veteran operator from the era of Assad's father. Maher al-Assad, the president's younger brother and Syria's second most powerful man, commands the main loyalist strike forces.

Syria: The Lebanese Hezbollah TV channel says the interior minister and Assad's brother-in-law have been wounded.

Syrian interior minister and Assad's brother-in-law Assef Shawkat wounded in Damascus explosion- Hezbollah's Al-Manar TV. — Reuters Top News (@Reuters) July 18, 2012

Hezbollah TV is now saying Assad's brother-in-law, Assef Shawkat, is dead. Reuters says the suicide bomber worked as a bodyguard for President Assad's inner circle.

Syria: The website of the government news agency, Sana, is inaccessible again today. It was brought down by a cyber-attack a few days ago but later re-appeared.

Syria: State TV says interior minister is injured but in stable condition.

Syria Activist Shakeeb al-Jabri reckons the attack was the work of the Free Syrian Army and he predicts the regime will launch a "massive retaliation" against rebel strongholds in the capital over the next few hours.

Jabri, who tweets under the name @LeShaque, has been monitoring Syrian state TV from neighbouring Lebanon.

He says the way the state media has covered the attack is unprecedented. Speaking before the state media confirmed the death of Assef Shawkat, he said:

The reaction of state media is the biggest question here. Typically this isn't the kind of thing they announce. They like to give the impression that all is fine. They didn't say it was a body guard. They said it was a suicide bomber who targeted the building, and the [only] casualty was Dawoud Rajha. State media hasn't elaborated on other casualties.

Asked to comment on speculation that the killing of the defence minister was a targeted to eliminate a potential defector Jabri said:

I'm not sure. They could have done it a lot more quietly. What they did today was create a media circus. It could have been an internal elimination ... nobody is reporting a loud explosion. My theory is that it wasn't an internal thing, it was the FSA or some third party group - one of those groups who have snuck into Syria. From what I've heard so far I suspect it was an IED, because a suicide bomber would have had to dive into the building and exploded themselves inside it. You would ask how the hell the would he get in the building?' This is a big development. It is likely to be used as an excuse to escalate the oppression campaign in Damascus. So I expect that by nightfall there is going to be a massive retaliation against the FSA in Damascus.

Syria: Al-Jazeera is reporting two claims of responsibility for the attack on Assad's inner circle: from the Free Syrian Army and also a group called the Islamic Brigade.

Hezbollah's TV station now says four top officials were killed: defence minister Dawoud Rajha, Assad's brother-in-law Assef Shawkat, interior minister Mohammad Ibrahim al-Shaar, and the head of the national security office.

Syrian TV has confirmed the deaths of Rajha and Shawkat.

Al-Jazeera also says the explosion in the meeting room was followed by gunfire.

News is breaking rapidly, but here's a summary of what we know so far:

• Syrian state television has announced the death of two key members of President Bashar al-Assad inner circle in a terrorist bomb attack against the national security building in Damascus. The blast killed defence minister Dawoud Rajha and his deputy Assef Shawkat - Assad's brother-in-law.

• Two groups have claimed responsibility for the explosions. Liwa al-Islam, an Islamist rebel group whose name means "The Brigade of Islam", said in a statement on its Facebook page that it "targeted the cell called the crisis control room in the capital of Damascus." The Free Syrian Army also claimed responsibility for the attack, according to spokesman Qassim Saadedine. "This is the volcano we talked about, we have just started," he said. Security sources have blamed the attack on a bodyguard for the regime's inner circle, according to Reuters.

• Several officials were also wounded in the attack, including intelligence chief Hisham Bekhtyar and the interior minister Mohammad Ibrahim al-Shaar. The blast occurred during a meeting of cabinet ministers and security officials, according to state TV.

• The Syrian government has vowed to wipe out those responsible, amid fears of increased bombardment against opposition strongholds. In a statement issued by the military it blamed the attack on "hired hands". It said it was "more determined than ever to confront all forms of terrorism and chop any hand that harms national security".

• Russia has submitted its own "enhanced" draft resolution ahead of a security council meeting, and signalled its opposition to a UK draft which gives the Syrian government 10 days to end the violence.Alexander Pankin, Russia's deputy ambassador to the UN, said: "We have taken into account [in the enhanced draft] concerns over humanitarian situation, human rights and localized ceasefire. This idea has been discussed by Kofi Annan with the Syrian leadership in Damascus. It seems to be rather effective."

Syria: Meanwhile, elsewhere in Damascus:

#Syria: MT @weddady AJA: explosions in the 4th Division base in #Damascus-- the regime's elite unit commanded by Assad's brother Maher — Borzou Daragahi (@borzou) July 18, 2012

4th Div. is the strongest in the Syrian Army, headed by Assad's sexually frustrated bro Maher Assad. The only Mechanized Division in Syria — ♕The 47th♕ (@THE_47th) July 18, 2012

Syria: State TV says the regime will announce a call-up of reserves tomorrow (which should allow enough time for any unwilling reservists to run away).

Syria: This map shows the Radwa area of Damascus where the attack on the national security bureau is said to have taken place.

Meanwhile, Wikimapia shows the location of the army's fourth division headquarters where there have been reports of explosions.

Syria: It is reported that army chief of staff Fahed al-Jasem al-Freij has been named as the new defence minister.

Syria: Britain's foreign secretary, William Hague, has condemned today's attack in Damascus, saying it "confirms the urgent need for a chapter VII resolution of the UN security council", the Press Association reports. He continued:

The situation in Syria is clearly deteriorating. All the members of the UN security council have a responsibility to put their weight behind the enforcement of joint special envoy Kofi Annan's plan to end the violence. We call on all parties to refrain from violence and for the Security Council to shoulder its responsibilities.

A chapter VII resolution would increase pressure on the Assad regime.

Former foreign minister Lord Malloch-Brown, speaking on BBC Radio 4, said today's attack was "an astonishing penetration of Syrian security", adding: "It will be a huge blow to their morale."

Syria: Several tweets claim that the first vice-president, Farouk al-Sharaa, has defected to Jordan. At present we have no reason to believe these are anything more than rumours. We're awaiting confirmation – or not.

Syria: Prominent activist Razan Ghazzawi is now liveblogging from the Midan area of Damascus. She begins:

I arrived Midan with a friend at 12:30 PM today 18-7-2012, there was a shooting very close to us but we managed to arrive safely. I cannot share my location with you in Midan, nor can I say who's with me here. We are safe so far. Clashes started early in the morning and it's still on, we sometimes hear explosions every now and then, the residents of area here are telling us there are BMB tanks shelling the center of the area. There are several checkpoints in the area, but the area we're in right now is relatively safe thus far, there are four people martyred today in Midan alone; 3 from Free Syrian Army and the fourth is a civilian- an old man we couldn't find his ID with him, we're in the process of getting his name.

Syria: The former defence minister and current assistant vice president, Hassan Turkmani, was also killed in the blast according to Reuters, citing a pro-government TV channel.

Syrian general Hassan Turkmani dies of wounds sustained in Damascus blast - Hezbollah's Al-Manar TV. Watch Reuters.com for updates. — Reuters Top News (@Reuters) July 18, 2012

Syria: "This is a situation that is rapidly spinning out of control," according to US defence secretary Leon Panetta.

Speaking to reporters he called on the international community to "bring maximum pressure on Assad to do what's right to step down and allow for that peaceful transition".

Syria: Anti-government protesters in Jarjanaz in the north-west province of Idlib have taken to the streets to celebrate the deaths from today's blast.

Footage from the town showed residents, including children, cheering and making victory signs. They also fired guns in the air in celebration.

Celebrations were also filmed in nearby Saraqab (via Said Benjamin).

Syria: Al-Arabiya has an unconfirmed report that a fourth senior member of Assad's inner circle was killed in the blast.

Hafez Makhlouf, head of the investigations at the #Syrian Intelligence Agency died in the Damascus explosion: Al Arabiya sources #AlArabiya — Al Arabiya English (@AlArabiya_Eng) July 18, 2012

Hafez Makhlouf is Assad's maternal cousin and brother of the powerful tycoon Rami Makhlouf.

Syria: There are numerous unconfirmed reports of large scale defections in the wake of today's attack.

The activist group, the Local Coordination Committees in Syria, says 60 soldiers defected with their equipment in Deir Baalba, Homs.

Cairo based activist Alexander Page tweeted:

BREAKING & CONFIRMED: defection of #Damascus military security official with control of 120 military tanks #Syria — Alexander Page (@AlexanderPageSY) July 18, 2012

Twitter user claiming to post updates on behalf of the Free Syrian Army, tweeted:

#Syria #Damascus 500 assad troops just defected near to Assads palace All Assad Forces urged to abandon this Dying Regime Save your selfs RT — riad al asaad (@fsa_hq_syria) July 18, 2012

Activist Ammar Kalo says it is impossible to confirm how much of this is simply rumour:

News of Defections EVERYWHERE .. cant keep track, and cant confirm which is true and whats a rumor. #Syria #Damascus #Homs #Idlib — Ammar Kalo█★★★█ (@MuhandisMundas) July 18, 2012

The new defence minister's first job has been to deny reports of defections:

#BREAKING: Syrian new Defense Ministerdenies reports of defections and described them as "anti-Arabism and fabricated" #Syria #Arab — Zaid Benjamin (@zaidbenjamin) July 18, 2012

Syria: Syrian TV has confirmed the death of Hasan Turkmani, Shakeeb al-Jabri and others report:

BREAKING #Syria TV now confirming that Hasan Turkmani has also died. — Shakeeb Al-Jabri (@LeShaque) July 18, 2012

Syria: An extraordinary video posted on YouTube today purports to show members of the FSA heading into battle.

The location seems to be Aleppo but some tweets suggest they are entering Damascus.

Syria: Kofi Annan has called for today's vote in the UN security council on Syria to be postponed, according to the Foreign Office.

Joint Special Envoy Annan has asked to delay today's draft #Syria resolution vote. With fellow co-sponsors we're considering that request. — UKUN_NewYork (@UKUN_NewYork) July 18, 2012

Earlier Russia's foreign minister Sergei Lavrov said a "decisive battle" was under way in Syria.

He added:

Adopting a resolution against this backdrop would amount to a direct support for the revolutionary movement. If we are talking about a revolution then the UN security council has no place in this. Instead of calming the opposition, some partners are fostering a further escalation.

Syria: Syrian TV has announced the death of the interior minister Mohammad Shaar.

Syrian TV confirms minister of interior is dead, killed in the explosion #Syria — Rula Amin (@RulaAmin) July 18, 2012

The announcement brings the confirmed deathtoll to four, according to state TV.

Earlier Shaar was reported injured in the attack.

The pro-government channel Dounia, denies that he was killed. It reports that he is in a stable condition, according to Said Benjamin.

There has been no more word on Assad's maternal cousin Hafez Makhlouf.

Syria: Analysts are wondering aloud about whether this represents the end of the Assad regime:

Salman Shaikh, director of the Brookings Doha Centre:

Boarding my flight. Wonder what will be of #Syrian regime as I open my phone in a few hours. — Salman Shaikh (@Salman_Shaikh1) July 18, 2012

Emile Hokayem, senior fellow for regional security at the International Institute for Strategic Studies, is as long-winded as possible in 140 characters:

Today's decapitation of Syrian security apparatus is not turning point but the acceleration+accentuation of the regime's downward trajectory — Emile Hokayem(@emile_hokayem) July 18, 2012

Chris Doyle, director of Council for Arab-British Understanding, tweets the reaction of his Syrian friends:

Sense from #Syria friends is one of total shock, mixed emotions, worry but a sense of a light at end of tunnel perhaps — Chris Doyle (@Doylech) July 18, 2012

Syria: Bambuser, the live streaming video site, has footage purporting to show celebrations in Damascus being protected by rebel gunfire.

Your browser does not support iframes.

After around 23 minutes the celebrations begin to turn ugly as some of the crowd begin throwing objects and insults at people off camera.

At around 27 minutes masked rebels are shown firing weapons behind parked cars.

Syria: The Obama administration says it's clear that Assad is losing control of Syria, Reuters reports.

The White House says it sees "real momentum" against Assad and stronger, more united opposition across Syria, it reported.

Reuters reports that a UN vote on whether the mandate of its monitoring force in Syria should be extended – due to take place later today in New York – has been cancelled.

Mohammad Ibrahim al-Shaar

Reports differ on the fate of the interior minister.

State TV reported that he had been killed.

The pro-government channel Dounia, denied that he was dead. It reported that he is in a stable condition.

Hassan Turkmani

The former defence minister and was known as the the regime's crisis management chief.

Until his death Turkmani was serving as an assistant to the country's vice president. In his mid-70s, Turkmani was close to the regime and took part in the crackdown against the uprising. Shortly after the revolt began in March last year, Assad sent Turkmani to Turkey for talks with officials there.

Assef Shawkat

Assad's brother-in-law and the deputy head of the armed forces, and his closest security adviser.

Shawkat, married to Assad's sister Bushra, was one of the most feared figures in the president's inner circle and had won the support of the clan's influential matriarch, Anisa. He was one of three central figures in the regime crackdown, along with Assad himself and his brother Maher. As Syria's overall security chief, he had key input into all military and intelligence operations. He is known to have survived an attempt to poison him in late May when a cook contaminated food that had been prepared for him and key members of the national security ministry.

Here's what we know about the four men reported dead so far:

Dawoud Rajha

Although he was the defence minister but that did not mean he was the most powerful security official. His identity as a Christian helped the regime present an image of multi-ethnicity.

As is the case in many ministries, there was an Alawite, President Bashar al-Assad's brother-in-law Assef Shawkat, in the number two position at defence, and his membership of the family network was far more important than title.

Furthermore, the defence ministry is less powerful than the interior ministry, intelligence service and Maher al-Assad's Republican Guard. But Rajha's presence around the table at the national security council reflected the fact that he wielded real clout in the apparatus.

We're continuing our live coverage over on this page – here's a summary what we know so far:

• Four senior members of the Bashar al-Assad's inner circle have been killed in a bomb attack on the national security building in Damascus, in what amounts to a grave crisis for the ruling regime. The blast killed defence minister Dawoud Rajha and his deputy Assef Shawkat - Assad's brother-in-law. Also killer were the interior minister Mohammad Shaar and the assistant vice president, Hassan Turkmani. The blast occurred during a meeting of cabinet ministers and security officials, according to state TV.

• Two groups have claimed responsibility for the explosions. Liwa al-Islam, an Islamist rebel group whose name means "The Brigade of Islam", said on its Facebook page that it "targeted the cell called the crisis control room in the capital of Damascus." The Free Syrian Army also claimed responsibility for the attack, according to spokesman Qassim Saadedine. "This is the volcano we talked about, we have just started," he said. Security sources have blamed the attack on a bodyguard for the regime's inner circle, according to Reuters.

• The US defence secretary, Leon Panetta, says the situation in Syria is "spiralling out of control". He called on the international community to "bring maximum pressure on Assad to do what's right to step down and allow for that peaceful transition" The Russian foreign minister, Sergei Lavrov says a "decisive battle" is under way in Syria. A UN vote on the future of its monitoring force in Syria, due to take place today, has been cancelled.

• The Syrian government has vowed to wipe out those responsible for the blast, amid fears of increased bombardment against opposition strongholds. In a statement issued by the military it blamed the attack on "hired hands". It said it was "more determined than ever to confront all forms of terrorism and chop any hand that harms national security".