The official number of civilians killed in the US-led coalition’s airstrikes in Syria and Iraq has risen to 220 amid fears for up to 750,000 people trapped in Mosul.

Humanitarian organizations have warned that the real total may be far higher, with monitoring group Airwars counting at least 2,400 innocent men, women and children killed in the anti-Daesh bombing campaign. 

US Central Command, which leaders Operation Inherent Resolve, confirmed 21 civilian deaths in nine new incidents in its latest round of investigations. 

“We regret the unintentional loss of civilian lives resulting from coalition efforts to defeat Isis in Iraq and Syria and express our deepest sympathies to the families and others affected by these strikes,” a spokesperson said. 

The deadliest single strike was in Mosul on 13 January, where investigators found eight civilians were “unintentionally killed” in an operation targeting Daesh fighters in a house. 

It was unclear whether the report described the same incident reported on the day by residents, who said up to 30 members of a Daesh commander’s family died when their house was bombed, despite the target not being inside. 

“During post-strike video analysis civilians were identified near the house who were not evident prior to the strike,” Centcom’s report said.