Syrian civilians flee from reported regime air strikes in the rebel-held town of Jisreen, in the besieged Eastern Ghouta region on the outskirts of the capital Damascus, on Feb 8, 2018. A fourth consecutive day of heavy regime bombing raids on the rebel-held enclave of Eastern Ghouta near Damascus killed 22 civilians on Feb 8, a monitor said. (AFP)

BEIRUT, Feb 8, (Agencies): The US-led coalition said Thursday it killed at least 100 pro-regime fighters to fend off an attack on its allies in eastern Syria, in one its deadliest confrontations yet with forces backing Damascus. The initial attack was carried out by forces loyal to President Bashar al-Assad on key oil and gas installations in parts of Deir Ezzor province controlled by US-backed Kurdish forces.The clash came against a backdrop of escalating tensions between Washington and Damascus over an uptick in the suspected use of chemical weapons by the regime and allied militia. Meanwhile, regime warplanes rained bombs for a fourth consecutive day on the rebel-held enclave of Eastern Ghouta, outside Damascus, where the death toll soared to more than 180 since Monday.According to the US Central Command (CENTCOM), coalition advisers were present in the area that was attacked by pro-government forces in Deir Ezzor province late on Wednesday. “The coalition conducted strikes against attacking forces to repel the act of aggression” against its own personnel and the Kurdish-led Syrian Democratic Forces (SDF) hosting them, it said. “We estimate more than 100 Syrian pro-regime forces were killed while engaging SDF and coalition forces,” a US military official said on condition of anonymity.The SDF and the coalition targeted the attacking forces with air strikes and shelling after “20 to 30 artillery and tank rounds landed within 500 metres (yards) of the SDF headquarters location”, the official said. According to the Syrian Observatory for Human Rights, which only confirmed 45 dead among pro-regime forces, the initial attack took place near Khasham. The head of the Britain-based monitoring group, Rami Abdel Rahman, said the aim of the attack appeared to be the capture of a key oil field and a major gas plant in an SDF-held area.The Omar oil field, one of the biggest in Syria, had a pre-war output of 30,000 barrels per day, while the Conoco gas field had a pre-war capacity of 13 million cubic metres a day. Regime and SDF fighters were involved in several skirmishes in the area last year, as they each conducted parallel operations against some of the Euro/KD 0.3680 Islamic State jihadist group’s last bastions.Damascus and the US-backed Kurdish militia once worked towards the same goal in the region but they were never allied, and the collapse of the IS “caliphate” has further strained an already frosty relationship. Syrian state media confirmed that dozens were killed in the clash but appeared to deny the forces were army soldiers, describing the victims as “popular forces”. According to the Observatory, the forces that launched the attack on SDF positions were local tribal fighters loyal to Assad and Afghan Shiite militia fighting alongside the regime.CENTCOM said the attack occurred eight kilometres (five miles) east of the “Euphrates River de-confliction line,” referring to a boundary agreed by Russia and the US, with the former’s area of operations west of the river and the latter’s to its east. IS jihadists were flushed out of their last strongholds in eastern Syria and over the border in western Iraq late last year. But the SDF continues to hunt down surviving jihadists who have reverted to a clandestine insurgency. Washington has recently ramped up the rhetoric against Damascus over its alleged use of chemical weapons, including on a number of occasions in January and February. Chlorine-filled munitions are reported to have been fired several times on rebel-controlled areas, including the enclave of Eastern Ghouta.Four days of ferocious Syrian government raids on the rebel-held enclave of Eastern Ghouta have killed more than 200 civilians, a war monitor said on Thursday. Syrian government troops have since Monday waged an intense air campaign on Eastern Ghouta, the only significant opposition pocket near the capital Damascus. Bombardment on Thursday alone killed 58 civilians including 15 children, according to the Britain-based Syrian Observatory for Human Rights.The deadliest strikes hit a market in the town of Erbin and killed 21 civilians including nine children. “These are the worst four days that Eastern Ghouta has ever gone through,” said Hamza, an overwhelmed doctor at the local Erbin clinic who was treating wounded patients. “From 2011 until now, there has never been the level of bombardment we’ve seen in the last 96 hours.” He described seeing shell-shocked children brought in to the clinic, sitting in silence even though they were badly wounded.“As a doctor, the hardest thing you can do is to treat your loved ones, your colleagues, your neighbours, your relatives,” Hamza said, breaking down. Syrian government warplanes have ratcheted up their bombardment of Eastern Ghouta this week, leaving dozens dead and hundreds in need of medical care. Regime bombing raids left 38 civilians dead on Wednesday, the Observatory said in a new toll. It came on the heels of the bloodiest day in months for Eastern Ghouta on Tuesday, when 80 civilians were killed in strikes. Jisreen was also hit heavily, with 17 civilians killed on Thursday. An AFP correspondent there said the strikes hit near a school, a market and a mosque, leaving vegetable stalls overturned and damaged.