Regime to intensify crackdown on protesters after claiming that dozens of government personnel were killed in Jisr al-Shughour

The Syrian government has vowed to retaliate after claiming that dozens of its police and security forces were killed in attacks in and around the north-western town of Jisr al-Shughour.

In an indication they will intensify the crackdown on protesters that has already killed an estimated 1,200 civilians, authorities rapidly upgraded the toll in the town 20 miles from the Turkish border.

The state news agency, Sana, initially said 28 personnel had been killed, including in an armed ambush and at a state security post. It revised the figure up to 43, 80 and then 120 within the space of an hour without an explanation. The claims could not be independently verified.

"We will act firmly and decisively based on the law [and] will never be silent over any armed attack that targets the country's security," the interior minister, Ibrahim Shaar, said in a statement broadcast on state television.

A military operation took place in the town as part of a wider crackdown on 12 weeks of protests calling for the end of President Bashar al-Assad's rule, although residents said the town was calm on Monday.

The regime and state media have little credibility, having waged an unprecedented war of disinformation while refusing to acknowledge a role in the crackdown, blaming the escalating violence on armed gangs and extremist insurgents.

Amateur footage and eyewitnesses have depicted scenes of plain-clothes security forces and the army shooting at peaceful protesters.

Activists and analysts suggested members of the security forces may have been killed but said that claims the killings had been carried out by armed gangs were intended to justify the crackdown. They pointed out that armed gangs never roamed Syria before the Arab spring.

A man identifying himself as First Lieutenant Abdul Razak Tlass denied in an interview on al-Jazeera on Monday evening that the regime was fighting armed groups. The soldier, believed to be from the extended family of former defence minister Mustafa Tlass who was one of the closest allies of Bashar's father Hafez, urged army officers to stand with the protesters.

A resident of Jisr al-Shughour told the Guardian on Monday there had been some clashes between plain-clothes security forces and the army over the weekend, but that this could not account for all the dead.

Activists have admitted that a small number of protesters, pushed to the extreme by over two months of a crackdown that has seen tanks and even helicopters bombard cities and towns, are fighting back, including in Jisr al-Shughour and Tel Kalakh.

Two men from Jisr al-Shughour said some protesters had returned fire when shot at by security forces in the past few days, but did not know of Sunday night's ambush.

Analysts suggest further explanations could include exaggerated numbers, the killing of plain-clothed security forces by accident by other forces or the deliberate killing of forces due to defections.

"We can't know who killed the security because no one is allowed in to see," said Rami Abdul-Rahman, of the London-based Syrian Observatory for Human Rights, which claimed at least 27 civilians and 13 security force personnel had been killed in Jisr al-Shughour over the weekend.

"You can't control people who see their relatives killed or tortured and not expect a small minority not to fight back, but it is all regime-stoked," he said.

Human rights organisations say more than 1,200 civilians, including 77 children, have been killed since the protests broke out in mid-March, while the government claims more than 200 of its personnel have been shot dead.

Two members of the security forces are reported to have been killed by mourners on Saturday in Hama, but some activists deny the claims.

Many say the Syrian regime is trying to provoke predominantly peaceful protesters to fight back to justify the state's crackdown, which has turned increasingly bloody as the government refuses to offer substantive reform. "The government, willing to kill citizens and provoke Israel, is turning a peaceful, legitimate uprising into chaos," said an analyst in Damascus.

Nidaa Hassan is a pseudonym for a journalist in Damascus