U.S. warplanes launched airstrikes Wednesday to support Iraqi forces in the fight to retake the city of Tikrit from Islamic State militants, American officials said. The U.S.-led coalition hit as many as a dozen targets in Tikrit as Iraqi forces shelled ISIS strongholds in the city, according to a U.S. defense official. President Obama approved the airstrikes at the request of Prime Minister Haider al-Abadi, The New York Times reported. The airstrikes are the first time the U.S. has engaged in the offensive due of concerns about supporting the Iranian-led Shiite militias, which are backing Iraqi troops in the mission. U.S. officials have stressed the bombing raids are supporting “Iraqi forces under Iraqi command,” said Lt. Gen. James Terry, the senior U.S. commander of the U.S.-led coalition.