Baghdad- ISIS on Sunday claimed an attack on US forces assisting Iraqi troops in the war on the militants in northern Iraq.

ISIS militants fired Grad rockets on American troops east of Tal Afar, a town still under control of the organization west of Mosul, said an online statement by the group.

According to Reuters, the American military had said earlier that two US service members had been killed and five injured during combat operations in northern Iraq on Sunday.

“Initial reports indicate the incident was not due to enemy contact,” said the statement from Centcom, the US military command in the Middle East.

It added that an investigation was under way, but gave no further details about what happened or where.

According to the website iCasualties.org, which lists coalition casualties in Iraq and Afghanistan, 11 American soldiers have been killed in Iraq this year.