More than 15 rockets hit the Taji military base in Iraq on Wednesday, killing two Americans and one British national, according to U.S. military officials cited by Reuters. At least 10 others were also reportedly injured in the attack. CNN reports that it was not immediately clear whether the Americans and British national were contractors or military personnel. It was also not immediately clear who was responsible for launching the rockets or how many people in total were killed. Roughly 6,000 U.S. military troops are stationed in Iraq. Kataib Hezbollah, which the State Department has designated a “foreign terrorist organization,” was behind a previous rocket attack on an Iraqi military base in December that killed an American contractor. Col. Myles Caggins, a spokesperson for the U.S.-led coalition, confirmed in a tweet that “15 small rockets impacted Iraq’s Camp Taji base hosting Coalition troops” but gave no further information on casualties.