Three people were killed when troops stormed the city of Hama in west-central Syria, under a barrage of heavy shelling on Tuesday, Syrian activists based in Lebanon told dpa.
"After storming the city of Homs, now is the turn of Hama," Omar Idlibi, a Syrian activist based in Lebanon told dpa.
"So far we have reports of three people killed and dozens wounded in the shelling," Idlibi said.
"(Syrian President Bashar) al-Assad's thugs are making house-to-house arrests in areas inside Hama, that has spiraled out of government control," Idlibi said.
He added that the city is now out of electricity and all telephone and internet connections have been cut.
Activists have declared the central city of Homs as a "humanitarian disaster stricken area, after around a week of tank bombardment that killed more than 110 people in the flashpoint city.
Homs province has been a major centre of resistance and reprisal against al-Assad's regime.
Damascus faces potential fallout from the Arab League for not implementing a peace intitiative proposed by the 22-nation body.
Last Wednesday, Syria informed the Arab League it accepts the initiative, which is aimed at ending eight months of violence that has killed according to United Nations estimates 3,000 people, among them 187 children.
However, security forces continued their crackdown on pro-democracy protesters calling for the ouster of al-Assad, as the government blames "terrorist groups" for the unrest.
Meanwhile, the Syrian National Council has called for a general strike on Thursday across Syria to protest what they described as "brutal killings" in Homs and Hama and also to urge the Arab League to help save the Syrian civilians.