Padangekspres.net-Syrian troops arrive in Istabraq. The village is near Jisr al-Shughour, the besieged town from where thousands of inhabitants have fled to Turkey. Photograph: Bassem Tellawi/AP
Syrian army tanks rolled into the besieged town of Jisr al-Shughour from two sides on Sunday, accompanied by machine gun fire and loud explosions.
Local co-ordination committees, which have been documenting anti-government protests, reported that the town was attacked from the south and east by troops in about 200 vehicles, including tanks. Blasts could be heard as helicopters clattered overhead.
The foreign secretary, William Hague, reacted to the attack by calling on the UN security council to proceed with a resolution condemning violence by Syrian troops against their own people.
However, in a Sky News interview, he said the likelihood of securing a resolution were on a "knife-edge" because of opposition from neighbouring Lebanon.
Hague also ruled out military action, saying there was "no prospect" of the UN authorising air raids.
The advance on Jisr al-Shughour was announced just over a week ago as vengeance for what the Syrian government claimed was the killing of 120 members of the military by "armed men".
Activists said the victims were members of the security forces who were shot by regime loyalists after they refused to fire on protesters. The town has now been sealed off by around 15,000 troops.
Syrian forces told an Associated Press reporter – who, despite a general ban on foreign journalists entering the country, was invited to travel with them as they entered Jisr al-Shughour – that troops were there to arrest "gunmen" in the largely evacuated town.
Jisr al-Shughour, in the north-west of Syria, is normally home to about 40,000 people, but thousands of inhabitants have crossed into Turkey in recent days, taking sanctuary in refugee camps. Many of those who remained behind fled on Sunday if they were able to do so.
One of the remaining residents – 39-year-old Hikmat, who was present when the Syrian army rolled in – reported seeing troops firing indiscriminately. He finally fled after being shot in the foot by government troops.
The region, near Turkey's border, has a history of hostility towards the Damascus regime and is posing the biggest challenge yet to President Bashar Assad's struggle to crush the anti-government revolt.
Reports emerged of government troops firing live rounds at large crowds who had gathered last Sunday in a large public garden in the centre of Jisr al-Shughour to mark the funeral of a man killed by security forces the previous day.
Abu Tahar, a 29-year-old ambulance driver being treated for gunshot wounds to his back at a hospital in Antakya, Turkey, said he was shot after arriving at the garden to help the wounded, and reported that bullets "were raining from everywhere".
Members of his family, who he has contacted by telephone since being evacuated, have confirmed that large numbers of security forces who had abandoned their posts in the hours following the massacre in the garden were shot at by soldiers loyal to the regime.
The Syria-based human rights activist Mustafa Osso said the army was conducting military operations in three areas in the Idlib province, including the towns of Maaret al-Numan, Jisr al-Shughour, and the nearby Jabal al-Zawiya, a mountain that includes several villages.
He reported that advancing troops were using heavy weaponry against hundreds of army defectors from the area, and said this was "the biggest and most dangerous wave of defections" since an uprising against Assad's regime began in mid-March.