Syria government forces retake Homs district
Syrian government forces have pushed rebel forces out of the Deir Baalbeh district of the city of Homs after several days of fierce fighting.
One activist group said that more than 200 civilians were killed by regime forces after the fighting, but the claim cannot be independently verified.
The death toll across Syria on Saturday was reported to be as high as 400.
The strategically important city of Homs has seen much of the heaviest fighting in Syria's 21-month conflict.
Residents of Deir Baalbeh were rounded up and forced into a petrochemical plant where they were summarily executed, according to the Local Coordination Committees (LCC), an opposition group based in Syria.
Women and children were among the dead, according to the LCC.
The Syrian Observatory for Human Rights (SOHR), a UK-based activist group, reported violence across Syria on Saturday, including in suburbs of the capital Damascus which have seen persistent clashes in recent weeks as the government attempts to wipe out the rebels' presence there.
The SOHR said it had not been able to get through to Deir Baalbeh to document the deaths there.Risk of 'chaos'
The latest violence comes after United Nations peace envoy Lakhdar Brahimi warned on Saturday of "hell" for Syria if no political solution was negotiated to the crisis.
Mr Brahimi, speaking after talks with the Russian foreign minister, said the conflict had become more militarised and sectarian.
It also risked bringing chaos to the region with neighbouring Lebanon and Jordan overrun by refugees, he said.
Mr Brahimi arrived in Cairo on Sunday for talks with the Egyptian President Mohamed Morsi.
Opposition groups say more than 44,000 people have been killed since protests against Syria's government began in March 2011.
Earlier this month the UN's refugee agency said more than half a million Syrians had fled to neighbouring countries.