Thousands of people have fled to the Turkish border from the last big opposition stronghold in northwestern Syria because of an intensified bombardment by Russian forces and the Syrian army, residents and rescue workers said on Friday. A long line of vehicles was seen on Friday leaving the opposition-held city of Maarat al Numan which has borne the brunt of the attacks, which included airstrikes, they said. “The exodus is in the thousands. It’s a humanitarian catastrophe, we are seeing people walking in the streets and people waiting near the homes for cars to take them out,” said Osama Ibrahim, a rescue worker from Maarat al Numan. Airstrikes killed six people overnight in Maarat al Numan and 11 were killed in villages in the area, rescue teams said. Syrian state media said the Syrian army had pushed into several villages southeast of Idlib. Rebel fighters, who say the Russian and Syrian forces are implementing a scorched earth policy as they advance, said villages seized included Um Jalal in southern Idlib province and Rabea and Harbiya in eastern Idlib. Russia and the Syrian army, which is loyal to President Bashar al-Assad, deny allegations of indiscriminate bombing of civilian areas and say they are fighting al Qaeda-inspired militants. Turkish President Tayyip Erdogan, who reached an accord last September with Russia to contain the fighting and whose country is seen by many civilians in opposition areas as a protector, has warned of a renewed refugee influx. Erdogan said on Thursday 50,000 people were fleeing Syria’s northwestern region of Idlib. He did not say whether any of the people fleeing had entered Turkey. Meanwhile, the Britain-based Syrian Observatory for Human Rights said on Friday that clashes between Syrian regime forces and armed groups in the countrys last major opposition bastion have killed more than 60 on both sides in the past 24 hours despite UN calls for de-escalation. The war-monitoring group said 38 militants and allied rebels had been killed in battles with regime forces in the northwestern province of Idlib since Thursday night. The fighting near the militant-held town of Maaret al-Numan also killed 23 Syrian regime loyalists, the Observatory said. Russian warplanes, meanwhile, pounded areas around Maaret al-Numan and the nearby town of Saraqib with a series of airstrikes, according to the war monitor. The Idlib region, which is home to some three million people including many displaced by Syrias civil war, is controlled by the countrys former Al-Qaeda affiliate. The Damascus regime has repeatedly vowed to take back control of it. Pro-government forces launched a blistering offensive against the region in April, killing around 1,000 civilians and displacing more than 400,000 people from their homes. Moscow announced a ceasefire in late August, but the Observatory says deadly bombardment and skirmishes have persisted. The United Nations this week condemned a deadly rise in violence in the area after the Observatory reported that regime airstrikes and artillery fire had killed 23 civilians on Tuesday. Najat Rochdi, senior humanitarian adviser to the UNs Syria envoy, called for "immediate de-escalation". Syrias war has killed over 370,000 people and displaced millions from their homes since it began in 2011 with the brutal repression of anti-government protests.