More than 100,000 people have been killed since the start of Syria's conflict over two years ago, an activist group said today.

The Britain-based Syrian Observatory for Human Rights, which has been tracking the death toll in the conflict through a network of activists in Syria, released its death toll Wednesday, at a time when hopes for a negotiated settlement to end the civil war fade.

It said a total of 100,191 had died over the 27 months of the conflict. Of those, 36,661 were civilians, the group said.

UN diplomat cites Syrian chemical weapons use Britain and the United States have notified the United Nations of 10 different incidents of alleged chemical weapons use by the Syrian government, a UN diplomat says. The diplomat, speaking on condition of anonymity because the incidents have not been publicly divulged, said the Americans and British have found no evidence that the opposition possesses or has used chemical weapons. The Syrian government initially asked for a UN investigation of an alleged chemical weapons attack on March 19 on the Aleppo suburb of Khan al-Assal that it blamed on the rebels. But it has refused to allow a UN investigation team into the country to conduct a broader investigation of other allegations of chemical weapons use, initially raised by Britain and France and then by the United States. Swedish chemical weapons expert Ake Sellstrom, who is leading the investigation team, was in Turkey on Sunday and Monday, reportedly talking to doctors who treated victims of chemical use, and is expected to produce an interim report on his findings, perhaps in the first few weeks of July, the diplomat said. –The Associated Press

On the government side, 25,407 are members of President Bashar al-Assad's armed forces, 17,311 pro-government fighters and 169 militants from Lebanon's Hezbollah, who have fought alongside army troops.

Deaths among Assad's opponents included 13,539 rebels, 2,015 army defectors and 2,518 foreign fighters battling against the regime.

Entry of the foreign media into Syria is severely restricted and few reports from the fighting can be independently verified.

Earlier this month, the United Nations put the number of those killed in the conflict at 93,000 between March 2011 when the crisis started and end of April this year.

The government has not released death tolls. The state media published the names of the government's dead in the first months of the crisis, but then stopped publishing its losses after the opposition became an armed insurgency.

The fighting has increasingly been taking sectarian overtones. Sunni Muslims dominate the rebel ranks while Assad's regime is dominated by Alawites, an offshoot sect of Shiite Islam.

It has also spilled over Syria's borders, especially into Lebanon, where factions supporting opposing sides have clashed in the northern city of Tripoli and in the eastern Bekaa Valley.

Lebanese are divided over Syria's civil war with some supporting President Bashar al-Assad's regime and others backing the opposition. More than 550,000 Syrians have fled to neighbouring Lebanon as a result of the war.

Masked men ambush bus in Beirut

Earlier this week, sectarian tensions drew Lebanon's weak army into fighting. Eighteen soldiers were killed in a two-day battle between the army and supporters of a radical Sunni sheik in the southern city of Sidon. The army had earlier reported 17 deaths and said Wednesday that another soldier died of his wounds in a hospital.

The conflict reached the capital Beirut on Wednesday when masked men ambushed a bus and attacked the approximately 30 people aboard with knives, a Lebanese official said. He said 10 people were wounded in the attack in the eastern part of the city, including five Syrians, two Palestinians and three Lebanese, the officials said. He spoke anonymously in line with regulations.

Lebanon's state-run National News Agency said the bus was carrying Syrians headed to a TV studio in the eastern Sunday Market district to take part in a cultural program. It said there were eight attackers, who fled the area.

Syria's conflict began as peaceful protests against Assad's rule. It gradually became an armed conflict after the Assad's regime used the army to crackdown on dissent and some opposition supporters took up weapons to fight government troops.

Even the most modest international efforts to end the Syrian conflict have failed. UN special envoy to Syria Lakhdar Brahimi told reporters on Tuesday that an international peace conference proposed by Russia and the U.S. will not take place until later in the summer, partly because of opposition disarray.

The fighting has increasingly been taking sectarian overtones. Sunni Muslims dominate the rebel ranks while Assad's regime is dominated by Alawites, an offshoot sect of Shiite Islam.

Sunni-majority Saudi Arabia is Washington's key ally and a foe of Iran. Tehran, a Shiite powerhouse, supports Assad.

Saudi Arabia is sending lethal aid to the rebels. The United States also said it will provide arms to the opposition despite the Obama administration's reluctance to send heavier weapons for fear they might end up in the hands of al-Qaida-affiliated groups. Russia, Assad's staunch supporter, has been providing his army with weapons.

Syrian minister lashes out at Saudi Arabia

In Damascus, Syrian Information Minister Omran al-Zoubi lashed out at Saudi Arabia, accusing the Gulf kingdom of backing "terrorists" after Riyadh condemned Damascus for enlisting fighters from its Lebanese ally in its struggle with rebels.

Damascus has previously blamed the Sunni Gulf states, who along with the United States and its European allies back the Syrian opposition, for the civil war.

The remarks by al-Zoubi were carried late Tuesday by the state agency SANA after Saudi Foreign Minister Prince Saud al-Faisal met with U.S. Secretary of State John Kerry in Jiddah and condemned Assad for bolstering his army with fighters from Hezbollah. Prince Saud charged that Syria faces a "foreign invasion."

Al-Zoubi fired back, saying Saudi diplomats have blood on their hands and are "trembling in fear of the victories of the Syrian army."

The Syrian military with Hezbollah's help captured the central town of Qusair earlier this month and says it is building on the victory to attack rebel-held areas elsewhere.

On Wednesday, the observatory said the Syrian regime has tightened its grip of the border area with Lebanon after driving rebels out of the town of Talkalakh, which had a population of about 70,000 before the conflict. The town is predominantly Sunni, but surrounded by 12 Alawite villages located within walking distance to the Lebanon border.

The government's takeover will likely impact rebels' ability to bring supplies, fighters and weapons from Lebanon.

Syrian state TV showed soldiers patrolling the streets of the town, inspecting underground tunnels and displaying weapons seized from the opposition. Talkalakh is located in the central Homs province, which links the capital, Damascus, with the Syrian coastal areas that are the Alawite heartland.