Syrian rights activists say an outbreak of sectarian fighting between supporters and opponents of President Bashar al-Assad has killed about 30 people in the central city of Homs.

The activists say the fighting began late Saturday when the dismembered bodies of three government supporters were returned to relatives in Homs. The three Assad loyalists belonged to the president's minority Alawite sect and had been kidnapped several days earlier.

Rights activists and residents say government loyalists responded to the killings by going on a rampage in predominantly Sunni areas of Homs, torching and breaking into Sunni-owned shops.

They say shooting also erupted in the city, although the source of the fire was not clear. Residents complained that Syrian security forces did not intervene.

The reports cannot be independently verified as Syria does not allow foreign media to report and travel freely. The fighting comes amid a more than four-month-long anti-government uprising against Mr. Assad.

Six more bodies were found Sunday in Homs, where Syria's majority Sunnis live alongside Alawites and other religious minorities. Witnesses say the city was calm on Monday but the mood was tense.

Syrian Observatory for Human Rights director Rami Abdul-Rahman says the fighting in Homs is a “dangerous” development that undermines the uprising against Mr. Assad's 11-year autocratic rule.

Mr. Assad has sent Syrian security forces into towns and cities across the country to crush the uprising. Western powers have condemned the violent crackdown and imposed sanctions on Syrian leaders.

British Foreign Secretary William Hague said Monday the 27-nation EU could impose further sanctions on Mr. Assad's government.

The EU and the United States already have imposed asset freezes and travel bans on the Syrian president and his aides.

Also on Monday, Qatar announced it was closing its embassy in Syria and pulling out its ambassador in protest of the Syrian crackdown.