An American civilian contractor was killed and a number of soldiers were lightly wounded in a missile attack targeting an Iraqi military base near the city of Kirkuk, north of Baghdad, on Friday evening, according to Reuters news agency quoted US officials.

For its part, the Iraqi Security Media Cell said that a number of mortar shells landed on Friday evening on the "Key One" base, which is located in the province of Kirkuk. Security sources in the governorate explained that the base, which is used as the headquarters of a group of American advisors working with Iraqi forces, was subjected to a major mortar attack.

The statement did not give further details. Sources told Reuters that Iraqi security forces found a Katyusha rocket launcher in an abandoned vehicle near the base. No one has claimed responsibility for the attack.

According to Iraqi sources, ISIS cells have been active in the region since the organization was defeated and the Iraqi government recaptured all of the territory it controlled in December 2017.

But a senior US military official said earlier this month that attacks by Iranian-backed groups on bases containing US forces in Iraq had increased and become more sophisticated, pushing all sides toward an out of control escalation.

The American official's warning came two days after four Katyusha rockets landed on a base near Baghdad International Airport, wounding five Iraqi counter-terrorism forces, in the latest missile attacks on bases that include members of the US-led coalition against ISIS.

Security sources said that the military base, 15 km northwest of the city, includes American forces, along with Iraqi forces from the Federal Police and the anti-terrorist agency.