The anniversary of 18-year-old Michael Brown's death in Ferguson, Mo., began with a solemn march in his honor and ended with a rowdy protest that was interrupted by gunfire. St. Louis County Police say an officer who came under heavy gunfire returned shots amid the protest. The police department tweeted that at least two unmarked cars were hit by gunfire. It wasn't immediately clear whether anyone was injured in the shooting, but minutes after the shots were heard, an AP photographer saw a man lying facedown, covered in blood, behind a boarded-up restaurant. It wasn't immediately clear how badly the man was injured. (More Ferguson, Missouri stories.)