Damaged buildings in the old city of Homs

AP

A Syrian official says gunmen have fired on a bus transporting workers to a blanket factory, killing four and wounding eight others.

He says the attack happened at the entrance of the central city of Homs on Sunday. No other details were immediately available, reports The Associated Press.

He spoke anonymously as he was not authorized to make press statements.

Meanwhile, Syria's state news agency says a suicide bomber crashed an explosives-laden sedan into a coffee shop at a Damascus residential neighbourhood, causing damage but no fatalities.

SANA says the explosion took place at dawn on the capital's Masseh highway.

An Associated Press reporter at the site says the blast destroyed a balcony and ripped off a building facade.

Syria's uprising, which started nearly 19 months ago, has become an all-out civil war.