Twelve members of a Syrian pro-regime militia were killed in clashes with rebels overnight in the central city of Homs, the Syrian Observatory for Human Rights said on Friday. The deaths came as regime forces pushed forward with an offensive intended to recapture several rebel-held districts of the city, the group said. \"Twelve members of the pro-regime People\'s Committees were killed... during fighting with rebel forces on the outskirts of the Khaldiyeh neighbourhood,\" the group said. The rebel-held district is one of several that regime forces have laid siege to for more than a year. The regime has increasingly used militia groups to bolster its regular forces in battles against rebel fighters seeking to overthrow Syrian President Bashar al-Assad. The Observatory, which relies on a network of activists, doctors and lawyers on the ground, said regime troops were continuing to shell the neighbourhood on Friday. At least 135 people were killed in violence across Syria on Thursday, the group said.