Coalition airstrikes have targeted a gathering of Islamic State leaders at a house in northern Iraq, a US defence official has said.

Senior IS officers were meeting in al Qaim, a town near Mosul which is under the Islamist group's control. After the strikes began, militants evacuated a nearby hospital and used loudspeakers to ask for blood donors.

The bodies of 50 militants have since been transported to a morgue in Mosul, according to Reuters.

Unconfirmed reports from the news agency suggested the leader of IS, along with his deputy, were killed in the attack.

It is unclear whether top commander Abu Bakr al Baghdadi was among the militants targeted, a US official said.

"We cannot confirm if ISIL leader Abu Bakr al Baghdadi was among those present," CENTCOM spokesman Patrick Ryder said.

Described as the world's most wanted man, al Baghdadi has declared himself the caliph, or supreme leader, of the vast areas of territory in Iraq and Syria under IS control.

Washington has offered a $10m (around €8m) reward for his capture.

The airstrikes also destroyed a convoy of 10 armed IS trucks, US Central Command said.

In a statement, its spokesperson added: "This strike demonstrates the pressure we continue to place on the IS terrorist network and the group's increasingly limited freedom to manoeuvre, communicate and command."

Meanwhile, a series of explosions killed dozens of people across Iraq, including one Briton, according to reports.

A further 21 people were killed and around 100 wounded when Syrian army planes bombed the IS-controlled northern Syrian town of Al Bab, the Britain-based Syrian Observatory for Human Rights said.

US President Barack Obama has authorised the deployment of up to 1,500 more US troops to bolster Iraqi forces, including into Anbar province, where battles with IS militants have been fierce.

A statement from Iraqi Prime Minister Haidar al Abadi's office said: "This step is a little late, but we welcome it."