The US military has acknowledged that aircraft of the coalition fighting so-called Islamic State (IS) in Iraq hit a location in west Mosul where dozens of civilians were reportedly killed.

It says an investigation is under way.

Meanwhile, thousands of Mosul residents have fled the areas held by IS, in fear of US-led air strikes and fierce fighting by Iraqi ground troops.

Residents say IS is using civilians as human shields, hiding in houses and forcing young men to fight.

The US Central Command said the planes acted at the request of Iraqi security forces. It did not name which country's aircraft carried out the attack.

In its statement, it said "an initial review of strike data" indicated that an air strike on 17 March was carried out in western Mosul "at the location corresponding to allegations of civilian casualties".

Read more:  BBC News