Two Britons were ‘caught up in’ the shocking shootings in Tunisia that left 22 people dead, the Foreign Office revealed last night.

Seventeen tourists were killed when gunmen stormed the country's national museum yesterday, while a security officer, cleaner, police officer and two gunmen also died.

The nationality of one of the tourists is still unknown, but the others are from Japan, Italy, Colombia, Spain, Australia, Poland and France, Tunisia's Prime Minister Habib Essid said.

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A wounded victim of the attack is evacuated by rescue workers outside the museum yesterday

At least six others were wounded in the attack. Tunisian authorities are now hunting several men believed to have helped carry out the massacre

Pictures from French TV show people fleeing from the museum with armed security services providing cover as they run up the steps

Tourists and visitors to the Bardo museum are evacuated from the area by security forces

Video showed gunmen in military uniform storm the Bardo Museum, killing mainly foreign tourists who were visiting the attraction's world renowned collection of Roman mosaics.

A Tunisian tourist guide told how he 'stared death in the face' as terrorists opened fire on his clients in the attack which saw people shot as they exited cruise ship buses parked outside the museum.

The gunmen, disguised as soldiers, then entered the museum and took 30 more tourists hostage before police swarmed the building and killed them in a shootout which also claimed an officer's life.

Local guide Walid told MailOnline: 'They opened up on anything that moved. The choice was to run away, or face certain death or injury. I helped my clients find shelter as best I could.'

Walid - who did not wish to give his surname for fear of reprisals - knew where all the emergency exits were in the museum, next to the Tunisian parliament, and directed many people to safety.

Eyewitnesses told how the killers picked off visitors one by one with bullets, while others hid behind pillars or fled in terror to escape.

Tunisians gather at Avenue Habib Bourguiba in Tunis to show solidarity with the victims of the attack

Tunisians light candles outside the National Bardo Museum where scores of people were killed

Approximately 1,000 Tunisians were seen demonstrating in Tunis against terrorism, following the attack

People hold banners and shout slogans during a protest against the terrorist gunmen attack in Tunis

Other people seen protesting against the terrorist attack in front of the Tunisian National Theatre in Tunis

A Foreign Office spokesman said: ‘We can confirm that two British nationals were caught up in the shootings in Tunis on Wednesday and that we are providing consular assistance.

PRO-ISIS TWITTER ACCOUNT ACCURATELY PREDICTS TUNISIA ATTACK HOURS IN ADVANCE A tweet sent from pro-ISIS Twitter accounts accurately predicted the Tunisia terror attack, raising the possibility the terror group were behind the atrocity. Sent just hours before the gunmen opened fire on the popular museum tone tweet read: 'Coming good news to Tunisia's Muslims, and a shock to the disbelievers and the hypocrites, especially those who claim to be cultured.' The tweet was sent from the account @riif0BA9, which regularly posts pro-ISIS messages, with particularly reference to militants originally from Tunisia. When news of the attack spread online, the tweet was re-posted by numerous other ISIS sympathisers, many of whom also lavished praised on the gunmen's choice of target. 'The selected location has great impact upon the tyrants & crusaders, parliament & museum; heart of sovereignty and tourism,' an ISIS support called @Ajnad30_moslim wrote. Advertisement

‘We are working with the Tunisian authorities as well as with contacts in the tourist industry to establish if any further British nationals have been affected.

‘Through our travel advice, we are urging people to exercise caution and follow the instructions of the local authorities.’

Forty-four people were injured in the attack, including 13 Italians, seven French, four Japanese, two South Africans, one Pole, one Russian and six Tunisians.

Britain’s Prime Minister David Cameron said on Twitter: ‘Appalled by sickening terrorist attack in Tunis - my thoughts are with those affected. UK stands ready to support Tunisia.’

UK tour operators confirmed that while thousands of customers are believed to be in the country, ‘very few’ are in the capital where the attack was carried out.

The attack was the first on a tourist site in Tunisia since democracy was introduced to the country following the Arab Spring of 2011.

Another eyewitness called ‘Nabila’ said police ‘tried to push everybody away', as snipers took up positions on roofs. She said she saw one man being arrested, 'and he looked to be about 25'.

Last night, thousands of people gathered in the capital of Tunis in a show of solidarity against the atrocity as world leaders united in their condemnation.

Speaking at the Louvre museum to call for international efforts to preserve the heritage of Iraq and Syria against extremist destruction, French president Francois Hollande said he had called the Tunisian president to offer support and solidarity.

'Each time a terrorist crime is committed, we are all concerned,' stated Mr Hollande.

French Prime Minister Manuel Valls said yesterday: 'We are condemning this terrorist attack in the strongest terms. We are standing by the Tunisian government.'

An injured person is transferred to Charle Nicol hospital in Tunis, on a stretcher flanked by medical staff

One injured woman looks happy to be alive after being caught up in the shooting in Tunisia which left at least 17 dead

Officials cover bodies at the scene of the shooting at Bardo museum in Tunisia where at least 17 foreigners were killed

Bullet holes are clearly visible through the windscreen of the Hope Travel bus outside the museum

Meanwhile US Secretary of State John Kerry said Washington 'condemns in the strongest possible terms today's deadly terrorist attack' and praised Tunisia's 'rapid response' to resolve the hostage situation and restore calm.

They opened up on anything that moved. The choice was to run away, or face certain death or injury. I helped my clients find shelter as best I could Walid, local guide

Mr Essid earlier warned there may be others, acting as accomplices to the gunmen, who remain at large.

He said: 'The terrorists fired randomly as they got off the buses. As they fled, they were hunted and chased down. There is a possibility, but it is not certain, that [the two gunmen] could have been helped.

'We are currently conducting extensive search operations to identify the two or three terrorists who possibly participated in the operation.'

It is believed several hundred managed to flee the museum, while another 20 to 30 were taken captive before anti-terrorist security forces raided the building.

It is unclear who the attackers were, but a video posted online in December attributed to Islamic State warned that jihadis would target the country.

Tunisian security forces patrol the perimeter of the museum as the hostages were held captive inside

Hostages, many of which were children, are rescued from the museum after being transported in a police vehicle

A member of the Tunisian security forces pumps his fists after the shootout ended in the death of two of the attackers

Anti-terrorist squad members surrounded the area with temporary barbed wire fencing

Armed soldiers with their guns drawn take up positions behind a short wall during the standoff

Twitter accounts associated with ISIS, based in Syria and Iraq, were described as overjoyed at the attack, urging Tunisians to 'follow their brothers,' according to Rita Katz of Site, a US-based organisation that monitors militant groups.

European Union foreign policy chief Federica Mogherini said 'terrorist organisations' were behind the attack.

She added: 'The EU is determined to mobilise all the tools it has to fully support Tunisia in the fight against terrorism.'

Mr Essid declared, in what is thought to be reference to the country's tourism industry: 'All Tunisians should be united after this attack which was aimed at destroying the Tunisian economy.'

This was backed by Karim Ben Sa'a, a manager in the tourism industry, who declared: 'This is a black day for Tunisia.'

'We are very sad for these tourists. They visit our country and it is so, so, sad to see them die. Our hearts are black.'

Three officers discuss the best method in which to deal with the hostage situation, in which seven tourists were killed

Police officers and locals take shelter behind a parked car and motorbikes during the tense standoff=

Mohamed Ali Aroui, an Interior Ministry spokesman, described the two attackers as 'Islamists' in local broadcasts, CNN reported.

We can confirm that two British nationals were caught up in the shootings in Tunis on Wednesday and that we are providing consular assistance Foreign Office spokesman

In the immediate aftermath of the attack, national guardsmen and anti-terrorist police quickly surrounded the hugely popular tourist site, which is visited by thousands of foreigners every year, including many Britons.

Fleets of ambulances could also be seen driving in and out of the museum grounds, as helicopters flew overhead.

The two heavily armed terrorists were holed-up inside with Kalashnikovs.

Interior Ministry spokesman Mohamed Ali Aroui said on Radio Mosaique that one of the dead was a Tunisian.

Farouk Afi, a blogger in Tunisia, was about to meet his friend in the museum when he heard the shots go off, according to the BBC.

He said: 'I was near, next door in the café, and I was going to meet with my friends. I heard it and I didn't know at that moment what it was, but the police told me go far from this place.

A wounded man is stretched into the back of an ambulance in the immediate aftermath of the attack

Tunisian security forces open a gate to allow an ambulance carrying the wounded to enter

A man is stretchered to safety while a heavily armed police officer stands guard to the left

At least six people were wounded and 17 tourists killed in the attack, carried out at midday yesterday

A spokesman for the Association of British Travel Agents (Abta) said: 'We are currently liaising with our members and the Foreign Office to assess the impact and understand if any British nationals have been caught up in the attack on the Bardo Museum in Tunis.

'Tunisia attracts over 400,000 UK visitors each year, with the vast majority travelling to resorts on the coast.

'Abta members have reported that they have currently approximately 6,500 customers in Tunisia, though very few of these are staying in Tunis. As a precaution many Abta tour operators have cancelled local excursions to Tunis due to depart over the next few days.'

Poland's prime minister has now revealed that some of the Polish victims of the attack were on a tour bus in front of the building when the gunmen opened fire.

Ewa Kopacz refused to give the precise number of Polish victims, saying figures were still being confirmed. Earlier yesterday, the Foreign Ministry said that three Poles were injured, while Polish diplomats in Tunis were working to confirm unofficial reports that four Poles had been killed.

Mrs Kopacz did say 20 Polish tourists are safe and sound.

Tunisian president Beji Caid Essebsi (second from right) is mobbed as he visits Charles Nicole Hospital to visit the wounded

It's believed more than 100 soldiers and armed police officers cordoned off the area following the initial attack

Police swarmed on the area after eight people were shot dead, with fears two of those killed were Britons

Tunisian authorities said their security forces engaged the terrorists inside the museum premises

A police officer takes aim from behind a wall after the militants fired indiscriminately at crowds outside the museum

Officers wearing body armour wait beside a bush as the siege unfolded yesterday afternoon

A group of hostages look through a window of the Bardo museum while being held captive by the attackers

And Piotr Henicz, deputy head of Polish tour company Itaka, said 36 tourists on a package holiday to Tunisia were visiting the museum when they came under attack.

Appalled by sickening terrorist attack in Tunis - my thoughts are with those affected. UK stands ready to support Tunisia David Cameron, British Prime Minister

The museum chronicles Tunisia's history and includes one of the world's largest collections of Roman mosaics.

Tunisia recently completed a rocky road to democracy after overthrowing its authoritarian president in 2011.

It has been more stable than other countries in the region, but it has struggled with violence by Islamic extremists in recent years, including some linked to ISIS.

It also has extremists linked to Al Qaeda's North Africa arm who occasionally target Tunisian security forces.

A disproportionately large number of Tunisia recruits have joined ISIS in Syria and Iraq.

Footage purporting to be taken during the police raid claimed to show hostages fleeing the building

The images, broadcast on Tunisian TV, showed men, women and children cowering as they ran from the gunmen

Three security officials stand guard outside the museum, which sits adjacent to the country's parliament

A soldier takes cover behind a short stone wall outside the museum

Security forces, armed with pistols and assault rifles take up positions against a wall

The museum, built within a 15th-century palace, is the largest museum in Tunisia, with collections covering two floors.

The museum is near the North African country's parliament, less than three miles from the city centre.

A new wing with contemporary architecture was built as part of a 2009 renovation, doubling the surface area. Some 8,000 works are displayed in the museum, according to the website.

The attack comes the day after Tunisian security officials confirmed the death in neighbouring Libya of a leading suspect in Tunisian terror attacks and the killings of two opposition figures in Tunisia.

Ahmed Rouissi gained the nickname of the 'black box of terrorism'. The information on his death was made public by security officials giving evidence in parliament and cited by the official TAP news agency.

Some of the Italians at the museum were believed to have been passengers aboard the Costa Fascinosa, a cruise liner making a seven-day trip of the western Mediterranean that had docked in Tunis.

An armed police officer takes cover behind a squad vehicle during the tense standoff

An injured man is carried into the back of an ambulance by Tunisian paramedics

A security forces helicopter carrying armed officers flies above the museum

A man is dragged to safety as groups of hostages flee the museum that is extremely popular with tourists

Three men carrying pistols race to the area as special forces cordoned off the site

Armed police swoop at the shooting scene at the Bardo museum Shooting at the Bardo Museum in Tunis

A special forces member pumps his fists in the air after the two gunmen were killed in a shootout with the authorities

Two balaclava-masked police officers stand guard while awaiting orders

Ship owner Costa Crociere confirmed that some of its 3,161 passengers were visiting the capital and that a Bardo tour was on the itinerary, but said it could not confirm how many, if any, passengers were in the museum at the time.

The cruise ship recalled all the passengers to the ship and was in touch with local authorities and the Italian foreign ministry.

Libya, which has devolved into chaos, is a source of major concern for Tunisia.

Also a major worry is the Mount Chaambi area on the border with Algeria where Al Qaeda in the Islamic Maghreb has reportedly been helping a Tunisian group which has killed numerous soldiers.

The shootings followed a string of attempted strikes against the authorities following recent raids on four alleged terror cells that have seen 32 suspects arrested.

There is also speculation it was revenge for the killing last weekend of Ahmed al-Rouissi, a Tunisian leader of a Libyan ISIS cell.

Tourists and visitors line up outside a tour bus before being evacuated from the area earlier yesterday

A man is stretched into an ambulance. While more than 20 died in the incident, at least six were wounded