Street violence continues to explode across Syria as local rights activists say security forces have swept through the capital, Damascus, and detained dozens of people.

Rights groups say the arrests took place late Saturday. The French news agency AFP quotes activists who say government troops set up roadblocks on routes into the Qabun district and set up positions in front of mosques with automatic rifles.

AFP also reports that activists say the Syrian army took control of several areas in the central city of Homs on Sunday, deploying heavily in the Duar al-Fakhura and al-Nazihin neighborhoods. Homs has been a flash point in protests against President Bashar al-Assad's government.

On Saturday, the streets in Homs appeared deserted following a large-scale security "crack down", an opposition group reported to the Israeli Haaretz newspaper. Heavy gunfire was reported. A Syrian military official denied reports that an explosion occurred early Saturday at a military academy in the embattled city.

The government said “saboteurs” trying to “hide behind” anti-government protests derailed a train near Homs. A state-run media report quoted an Interior Ministry official as saying “criminals” ripped up a section of track, causing the derailment and a fire that killed the train's driver and injured a number of passengers.

About 480 people were on board the train, which was heading from the northeastern city of Aleppo to Damascus. Rights groups say Syrian forces have killed at least 1,400 civilians during the government's crackdown on demonstrations, while the government has blamed much of the violence on terrorists and Islamists.

"The model of co-existence in Syria is being targeted by the incidents that the country is witnessing," presidential advisor Buthaina Shaaban told a gathering of Syrian expatriates in Damascus. 

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

A prominent Syrian rights blogger wrote, today "a terrible crackdown and assault is being planned for Homs soon."

See GlobalPost – Child Victims of Syria 

"Thirteen-year-old Hamza al-Khatib made worldwide headlines and became a symbol for the uprising when his family was handed back his tortured and broken body after a month in the custody of security forces," the blog said.