INVER GROVE HEIGHTS (AP) -- Two teenagers have been charged in connection with a fatal melee that involved rival groups on a party bus in Inver Grove Heights.

The boys, ages 16 and 17, are charged in juvenile court with second-degree assault and first-degree riot. The 17-year-old is still at large.

Authorities say the rival groups involving 40 to 50 people argued on the bus. Fighting erupted as they were getting off the bus in a movie theater parking lot early Saturday, then gun shots were fired. Nineteen-year-old Billy Ray Nobles was killed. A 16-year-old was wounded.

The Dakota County Attorney's Office says which teen fired the fatal shot has not yet been determined, but that murder charges could follow.