A branch of the Islamic State in Yemen claimed responsibility for a series of car bombings here in the capital that killed at least 30 people on Wednesday, adding a new layer of peril to a city terrorized for months by airstrikes as well as by antiaircraft fire that has fallen on civilian homes. The bombings, outside mosques where many Shiite Muslims worship and a headquarters of the Houthi rebels, were the deadliest attacks claimed by the Sunni extremist group since March, when suicide bombers killed more than 130 people at two Shiite mosques here. The March attacks helped accelerate the country’s slide toward civil war, sharpening sectarian tensions and aggravating the confrontation between the Shiite Houthi rebels, who are from the country’s north, and supporters of President Abdu Rabbu Mansour Hadi, who was ousted by the Houthis. Saudi Arabia entered the war days later, beginning […]