Washington (AFP) – A member of the US military was killed Thursday in a bomb blast north of Mosul, a senior US defense official said, as Iraqi forces in the region continued their push on the city.

The official told AFP that the service member had died in what were likely “Mosul-related” operations, but did not provide additional details.

More than 100 US troops are advising Iraqi security forces and Kurdish peshmerga as they advance toward Mosul, the Islamic State group’s last stronghold in Iraq, on multiple fronts.

Officials did not immediately identify the service member and the US-led coalition fighting IS said further information would be released “as appropriate” — additional details often depend on when family members are notified of the death.

An unnamed US official cited by CNN said the service member was medevaced off the battlefield but later died from the wounds. No other US troops were wounded, CNN said.

The death is the fourth time a US military member has been killed in combat in Iraq since operations against IS began there in 2014.

In May, Navy SEAL Special Warfare Operator 1st Class Charles Keating was fatally shot during a pitched battle with IS near the village of Tal Asquf, north of Mosul.

In April, Staff Sergeant Louis Cardin was killed by an IS rocket attack that also wounded eight Marines at an artillery position in the Makhmur area of northern Iraq.

And in October last year, Master Sergeant Joshua Wheeler, an American special operations soldier, was killed during a joint raid with Kurdish forces against IS in Hawijah, a northern Iraqi town.

In the biggest Iraqi military operation in years, forces have retaken dozens of villages, mostly south and east of Mosul, and are planning multiple fresh assaults.