A 15-year-old boy died after being shot in the stomach at a downtown Brooklyn park minutes after leaving school, police said.

Cops responding to a call about the shooting in McLaughlin Park, near Tillary and Jay streets, around 1:45 p.m. Wednesday found the boy shot. He was taken to a hospital with critical injuries and later died.

According to investigators, witnesses reported seeing two people approach the teen as he sat with two girls on a park bench after school. It's not clear where he attended school. New York City public schools start Thursday but others outside the district opened earlier in the week. Words were exchanged, then the argument turned into a physical fight.

At some point, a gunman wearing all black pulled out a gun and fired once, hitting the 15-year-old, two senior police department sources with direct knowledge of the case said. At this point, the sources say investigators are looking into whether the initial argument may have been gang-related. But they're keeping all avenues open.

"We are going to go back to school, look at school, talk to people at school. See if there was any argument at school during the day. We're also looking for any of those witnesses who were in the park," NYPD Chief of Detectives James Essig said.

Police say that there were around 30 people at the park around the time of the shooting and urge anyone who saw anything to call Crime Stoppers at 1-800-577-TIPS.