Seven mortar attacks injured four at the Al-Balad US airbase in Iraq on Sunday.

Al-Arabiya reported:

The military sources said the mortar bombs fell in the base’s runway inside the base, which is located in Salah al-Din province, 80 km (50 miles) north of Baghdad.

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A majority of US airmen stationed at the Balad air base had already left, the military sources said, following tensions between the US and Iran over the last two weeks.

Military bases hosting US troops have been subject to volleys of rocket and mortar attacks in recent months that have mostly wounded Iraqi forces, but also killed one American contractor last month.