A US soldier was killed alongside a British counterpart during a joint training exercise in Iraq, officials said.

The service members were killed Sunday at an air base in Irbil in the semi-autonomous Kurdish region of, where the US has maintained a presence, according to US Army Central Command and the UK’s Ministry of Defense, neither of which provided details on the circumstances of the fatal incident.

“The training was conducted with our British Army partners who also lost a soldier,” US officials said in a statement to Stars and Stripes. “The incident is under investigation.”

The US Army said it would be withholding the soldier’s identity for 24 hours.

British military officials also confirmed “with deep regret” that one of its soldiers was killed in a training accident in northern Iraq.

“Our thoughts and sympathies are with the family and friends at this time,” the agency said.

The US has been gradually reducing troops deployed to fight ISIS in Iraq, but American forces have retained a presence in the Kurdish region as the U.S. seeks to strengthen ties with the Kurds.

The deaths come nearly a month after two American soldiers died after falling off a cliff while on an off-duty recreational hike in Morocco. 

They were reported missing May 2 after participating in African Lion, an annual multinational military exercise.

With Post wires