From ABC News.

Members of The Church of Jesus Christ of Latter-day Saints in Grand Blanc, Michigan, were about a half hour into their Sunday morning service when they described hearing a "big bang" followed by gunfire.

A 40-year-old man wielding an assault rifle rammed his pickup truck through the front doors of the church and opened fire on "hundreds of people" at the service, seemingly shooting people indiscriminately inside the chapel, according to police.