BEIRUT: Daesh has killed 41 US-backed fighters in Syria who are battling to oust the extremists from their eastern holdout of Hajin on the Iraqi border, a war monitor said Saturday. Daesh late Friday dispatched suicide bombers as part of a counter-attack against the Syrian Democratic Forces, said the Britain-based Syrian Observatory for Human rights. The SDF fighters, who are backed by US-led coalition air strikes, were killed overnight, the Observatory said. In a statement on the Telegram messaging app, Daesh said it had attacked the village of Sousa late Friday and detonated a car bomb near the village of Al-Baghuza further south, down the Euphrates river. The SDF last month launched an offensive against the militants in the Hajin pocket on the eastern banks of the Euphrates, in Deir Ezzor province. Daesh has staged a bloody fightback. Since September 10, 270 SDF fighters and 496 Daesh militants have been killed in the offensive, the Observatory says. The coalition estimates that 2,000 Daesh fighters remain in the Hajin area. Last week, the Observatory said coalition air strikes had killed 41 civilians in Sousa, 10 of them children, on October 18 and 19. But the coalition said it had targeted a Daesh command post on October 18, and denied carrying out any strikes in the area the following day. Daesh overran large swathes of Syria and neighbouring Iraq in 2014, proclaiming a "caliphate" across land it controlled. But the extremist group has since lost most of that territory to various offensives in both countries. In Syria, its presence has been reduced to parts of the vast Badia desert and the Hajin pocket. Syria"s war has killed more than 360,000 people since it erupted in 2011 with the brutal repression of anti-government protests.