Syrian activists say soldiers backed by tanks have fired on citizens during a raid in the flashpoint city of Hama, killing at least 45 people.

Activists say the sound of machine guns and tank shells echoed across the city Sunday. Medical officials say hospitals are overrun with scores of wounded people and are in desperate need of blood donations. The death toll is likely to rise.

Troops reportedly started their attack at dawn Sunday, firing randomly and breaking down road blocks erected by civilians to keep troops out of the city.

Citizens have held large protests against President Bashar al-Assad in Hama, an important city in the history of Syrian resistance. In 1982, President Bashar al-Assad's father used military force to silence a rebellion there, killing thousands.

Meanwhile, in the country's south, residents say security forces killed three people and wounded several others as they stormed the village of al-Hirak. They say forces also arrested more than 100 people in the early Sunday raid.

Activists say President Assad is trying to crush the largely peaceful uprisings against his government that broke out across much of the country in March.

Rights groups say Syrian forces have killed at least 1,600 civilians during the government's crackdown on dissent. The government has blamed much of the violence on terrorists and militants who it says have killed hundreds of security personnel.

It is hard to verify accounts of the unrest in Syria because the government has barred most foreign media from reporting and traveling freely in the country.