The Imam Hussein mosque in Iraq’s Diyala province has had a bad string of luck, and it just got worse. A suicide bomber struck the Shiite mosque Thursday, killing at least 12 and injuring dozens more. The attack, which could reawaken sectarian violence, was apparently a meeting between Sunni and Shiite clerics that was intended to demonstrate that sectarian feuds were fading. It’s the fifth attack at the mosque in the last five years. Meanwhile, a car bomb in another province killed six, including a police chief. There’s been a sharp downturn in sectarian violence since Iraq’s civil war two years ago, but lately tensions have escalated.