At least 10 civilians were killed in an air strike on a market in Syria's rebel-held north-west region on Monday, Syrian opposition activists said. The air strike came amid an increase of violence in Idlib province, the last opposition stronghold where fighting between government and opposition forces killed scores of fighters on both sides over the weekend. The Britain-based Syrian Observatory for Human Rights said the morning air strike on the town of Maaret Al Numan killed 10 and wounded others. The Aleppo Media Centre, an activist collective that monitors rebel-held areas in northern Syria, also said 10 civilians were killed and dozens were wounded. “The bombardment of the market that was packed with civilians led to a massacre and wide destruction,” the Syrian Civil Defence, a volunteer rescue group also known as White Helmets, said on its Facebook page. The group put the death toll at nine civilians, including two women, with 13 others wounded, including two children. It posted photos of its paramedic removing bodies from the market, including a decapitated man lying in a pool of blood. The Observatory and the Civil Defence reported another air strike on the nearby town of Saraqeb that killed and wounded several people. Syrian troops launched a four-month offensive earlier this year against Idlib, which is dominated by Al Qaeda-linked militants. About 1,000 civilians were killed in the fighting and hundreds of thousands forced to flee their homes. A Russian-backed ceasefire halted the advance at the end of August, but in recent weeks it has been repeatedly violated. The Observatory said regime forces and armed groups were locked in heavy clashes on the edge of Idlib. "Fighting raged at dawn Monday on several axes in the south-eastern Idlib countryside," the group said. It said the battles were the heaviest since the ceasefire began, with 51 regime fighters and 45 of their opponents killed over 48 hours. The Idlib region is home to about three million people, including many displaced from other parts of Syria during the country's eight-year civil war. More than 370,000 people have died and millions have been forced to flee their homes since the war began in 2011 with the brutal repression of anti-government protests.