ST. LOUIS COUNTY, Mo.—Two teenagers are dead after a shooting in Olivette overnight. Monday afternoon, St. Louis County Police said its preliminary investigation reveals a 16-year-old man and an 18-year-old man were involved in an altercation at an apartment building in the 9400 block of Olive Blvd. 

Police say the 16-year-old shot the 18-year-old then left the building into an open field. 

The department says officers responded to a call for service just before 1 a.m. and, while canvassing the area, heard a gunshot. Officers thought they were being fired upon, according to St. Louis County Police, and called for additional help. 

Police say that gunshot is now believed to have been a self-inflicted gunshot fired by the 16-year-old. 

The circumstances surrounding the shooting are still unclear.

Olivette Police requested the St. Louis County Police Department’s Bureau of Crimes Against Persons to take over the investigation. 

Contact police at 636-529-8210 to speak with investigators if you have any information. To remain anonymous or potentially receive a reward, please contact CrimeStoppers at 1-866-371-TIPS (8477).