Residents of the Iraqi city of Mosul said up to 30 civilians were killed in an airstrike on a district held by Daesh this week.
The witnesses said it was not immediately clear if the attack was carried out by the US-led coalition fighting Daesh militants, or by air assets backing Iraqi forces that have been making punishingly slow advances against the extremist group in the city.
They said they saw at least three missiles hit the western Mosul Al-Jadida area on Thursday, in a raid that appeared to target the house of senior militant Harbi Abdel Qader.
He was not in the building at the time, but several members of his family died, one resident said late yesterday.
The Iraq Body Count (IBC), a group run by academics and peace activists that has been counting violent deaths in the country since 2003, said 21 to 25 civilians were reported killed on Thursday in a strike on that area.
The entirety of all areas of Mosul west of the Tigris River, which bisects the city from north to south, are still controlled by the ultra-hardline militant group. Daesh also still controls or is contesting much of Mosul's eastern districts.
The government claims that nearly all of eastern Mosul is under its control three months into the offensive, although analysts have pointed out that there is a difference between "presence" and "control".
The Mosul campaign, involving a 100,000-strong alliance of US and Iran-backed Iraqi government troops and militarised police, Kurdish Peshmerga and thousands of Shia jihadists, is the most complex battle in Iraq since the US-led invasion in 2003.