Syrian army tanks shelled the Bab Amro residential district in the country's third largest city of Homs on Wednesday, a human rights campaigner in the city said.
"Homs is shaking with the sound of explosions from tank shelling and heavy machineguns," said Najati Tayrara.
Earlier this week, Syrian security forces arrested scores of people in Homs and in Baniyas, two restive cities where President Bashar Assad has sent troops to crush a seven-week-old revolt against his authoritarian rule.
The Syrian Observatory for Human Rights said people were detained in the central cities on the Mediterranean coast -- the latest focus of Assad's escalated crackdown against protesters, as well as other regions.
Meanwhile, the European Union member states have agreed to issue a weapons embargo against Syria and impose sanctions upon 13 of its nationals, paving the way for the restrictive measures.
The embargo is meant to block weapons "that could be used for internal repression" from being exported to Syria, the European Council said late Monday.
Syria's upheaval began on March 18 when protesters, inspired by revolts across the Arab world, marched in the southern city of Deraa. Assad initially responded with vague promises of reform, and last month lifted a 48-year-old state of emergency.
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