BAGHDAD (AP) — Iraq's military on Thursday said it opened an investigation into a rocket attack hours earlier that killed three servicemen, including two Americans, at an Iraqi base housing coalition forces.

At least 12 coalition personnel were also injured late Wednesday by a barrage of rockets targeting Camp Taji base, located 27 kilometers (17 miles) north of Baghdad, according to a U.S.-led coalition statement. A truck rigged with 107 mm Katyusha rocket launchers was discovered by Iraqi security forces a few kilometers (miles) from the base following the attack.

A military statement from I...