ST. LOUIS -- An overnight shooting in a downtown St. Louis office building killed a 17-year-old and wounded nine other teenagers, the city's police commissioner said Sunday.

St. Louis Metropolitan Police Commissioner Robert Tracy identified the victim who was killed as a 17-year-old.

Tracy said victims ranging in age from 15 to 19 suffered gunshot wounds. Some were shot just once or grazed; others were hit multiple times.

A 17-year-old girl was trampled as she fled, seriously injuring her spine, Tracy said.

Police believe teenagers were having a party in an office space on 14th Street and Washington Avenue when the shooting broke out around 1 a.m. Sunday. Shell casings from AR-15-style rifles and other firearms were scattered on the ground.