Reports from the Syrian city of Hama say at least 130 people have been killed after tanks stormed the city to crush demonstrations against President Bashar al-Assad's rule.
Government forces have been besieging the city for almost a month. The tanks moved into Hama at dawn on Sunday.
But the city was reported to be quiet by early evening, and that the tanks had pulled back to the city's perimeters after failing to gain control of the centre.
The BBC reports the government is signalling that it will not tolerate large-scale unrest ahead of the holy month of Ramadan, during which the unrest is expected to increase.
Residents say hospitals are overflowing with casualties.
A correspondent says the people remain defiant, with some still in streets shouting: ''We will not be killed again,'' a reference to a massacre there in 1982.
The president's father, the late Hafez al-Assad, sent troops to crush an uprising in Hama in 1982. Up to 30,000 people were killed.
The government has defended its latest actions. A statement reported by the Sana news agency said that armed groups had ''set police stations on fire, vandalised public and private properties, set roadblocks and barricades and burned tyres at the entrance of the city''.
Most foreign media is banned from Syria, making it difficult to verify reports.
Ramadan begins on Monday.