Syrian troops stormed houses in the city of Hama on Monday as thousands of residents took to the streets shouting "God is greater" in defiance of a government crackdown on recent large protests, residents said.
"At least 30 buses carrying soldiers and security police entered Hama this morning. They are firing randomly in residential neighbourhoods," one of the residents, a workshop owner who gave his name as Ahmad, said by telephone.
He said he had seen dozens of soldiers surround a house in the Mashaa neighbourhood and make arrests. Young men, some carrying stones, blocked roads leading to central neighbourhoods with burning tyres and garbage containers.
Tanks deployed in Hama on Sunday but later pulled back, residents said, two days after the city witnessed the largest protest against the 11-year rule of President Bashar al-Assad since an uprising demanding political freedoms and Assad's removal began nearly four months ago.
The security forces' presence had lessened in Hama since they killed at least 60 protesters in the city a month ago in one of the bloodiest days of the uprising.
Demonstrations have swelled in numbers since then, witnesses have said, with at least 150,000 people assembling at a square on Friday in a rally demanding the removal of Assad, whose father, the late Hafez al-Assad sent troops to Hama in 1982 to crush an armed Islamist uprising.
That attack killed many thousands, and possibly up to 30,000, making the city synonymous with the bloodiest event in Syria's history since the Western colonial powers carved the country out the remnants of the Ottoman empire in 1920.