The teenager was reportedly killed at the Mobil gas station in the suburb Berkeley, St. Louis.
Social media users posted photos and videos of the victim’s emotional mother bursting into tears the moment she learns her son is dead, RT reported.
“They started shooting,” Toni Martin, the teen’s mother told reporters.
She added that her son was with his girlfriend at the time of the incident. The girlfriend remains at the scene, but won’t speak to reporters.
"That’s my baby,” Toni Martin was crying over and over again.
Martin attended Jennings Senior High School in St. Louis, Missouri, according to Twitter users.
The body, covered in yellow paper, was seen in numerous photos from Twitter user accounts.
The medical examiner has reportedly arrived at the scene of the accident. Police authorities have not yet commented on the alleged incident.
Dozens of Twitter users claim Martin was unarmed when he was shot. People are gathering at the scene, demanding police explain what happened.
They are shouting “Innocent people!” and “What is that?”