More than 10 mourners were killed at a funeral for another 10 people who were killed by security forces in Homs on Monday, the Local Coordinations Committee, an activists group, said. Syrian authorities have expelled most foreign journalists, making it hard to verify activist accounts or official statements.

"We could not bury the martyrs at the city's main cemetery so we opted for a smaller cemetery near the mosque, when the militiamen began firing at us from their cars," one mourner, who gave his name as Abdallah, told Reuters by telephone.

He said the bodies had been taken to Khaled Ibn al-Walid mosque in the eastern Khalidiya district of the city. "Khalidiya is totally besieged by the military. We are cut off from the rest of Homs as if we are a separate country."

Homs has been a major centre of protests against Assad's rule and tension has run high between the majority Sunni inhabitants and members of the Alawite minority, the same sect as Assad.

Khalidiya is inhabited by members of Sunni tribes from rural Homs while the nearby Nozha neighbourhood is home to most of the country's security forces and militiamen, from the Alawite sect.

The 16 deaths reported in Homs' Khalidiya and Bab Amr neighbourhoods on Tuesday brought the total death count since the weekend to at least 33, activists and residents said.

Another resident said: "There are troops and armoured vehicles in every neighbourhood. The irregular forces with them are death squads. They have been firing indiscriminately since dawn with rifles and machineguns. No one can leave their homes."

Troops and tanks first entered Homs, 165 km (100 miles) north of Damascus, two months ago and occupied the main square after large protests demanding political freedoms.

Homs, the hometown of Assad's Sunni wife Asma, has seen an influx of Alawites in the last 20 years as the community tightened its grip on security and public jobs.

The Syrian National Human Rights Organisation said seven people were killed over the weekend in attacks by security forces. The Syrian Observatory for Human Rights said the bodies of 30 people were found in Homs over the weekend, and that some were mutilated.

"After failing to ignite a sectarian civil war, the regime is expanding military operations to subdue the mass protests in Homs," Observatory director Rami Abdel Rahman told Reuters.

Human rights organisations say troops, security forces and militiamen killed at least 1,400 civilians in Syria, adding that more than 12,000 Syrians and security personnel who refused to fire at civilians had been shot dead.

Syrian authorities blame "armed terrorist groups" with Islamist links for the violence and say at least 500 policemen and soldiers have been killed since March.
Assad had described the uprising as a foreign conspiracy to sow sectarian strife. His opponents argue that the president has been playing on sectarian fears to maintain Alawite support and keep power for his family, which has ruled Syria for 41 years.

Once courted by the West as a possible moderate in the region, Assad is becoming increasingly isolated internationally, with Iran's Shi'ite clerical rulers maintaining their support, to the disquiet of Syria's majority Sunnis.

Diplomatic pressure mounted on Assad on Monday after Qatar, previously a major supporter, shut its embassy in Damascus and the European Union said it was considering tougher sanctions.

Qatar was a major backer of Syria until protests broke out in March, but relations deteriorated when Sunni Muslims began to be killed by Assad's security forces, whose leaders, like the president, belong to the minority Alawite sect.

In the tribal province of Deir al-Zor in eastern Syria, residents of Albu Kamal, on the border with Iraq, said security had eased its grip after holding talks with the troops. Notables from the region want to avoid an assault after defections among security forces who had tried to quell street demonstrations.

Thousands of people took to the streets of Albu Kamal in a night demonstration on Wednesday demanding Assad's removal, activists said. They added that large protests also continued across Deir al-Zor, in the Qaboun district of Damascus and in other towns and cities across the country.