COUNTRY CLUB HILLS, Illinois (WLS) — A dispute between parents escalated into a deadly shooting outside a south suburban high school on Saturday, a school district said in a letter to families.

Prairie-Hills Elementary School District 144 told families that the Prairie Hills Junior High boys basketball team was competing in a tournament at Hillcrest High School in Country Club Hills on Saturday afternoon.

The Cook County medical examiner confirmed there was at least one death related to the incident.

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The shooting just before 1:30 p.m. in the school parking lot, the school district’s letter said.

Bremen High School District 228, Hillcrest High School’s district, also sent a letter to families, saying “a parent attending the game from a neighboring community has become a victim of gun violence,” calling the shooting “a tragic incident “.

Witnesses told ABC7 the basketball tournament had just ended when a parent was shot and killed in the parking lot.

“A kid had a great game … he’s feeling good about himself and now he’s turning that happiness and joy around to be at the hospital around his family,” local activist Stringer Harris said.

Police were not releasing many details Saturday afternoon or if anyone had been arrested, but an ABC7 crew from Hillcrest High School saw a homicide detective at the scene.

“It’s sad … not only is this my former high school … I’m a mentor here every week,” Harris said. “I’m here at this school to teach about gun violence, and it’s sad to see this happen once again here on this campus.”

The shooting comes just one year after Hillcrest High School freshman Marshawn Mitchell was shot and killed after a homecoming football game.

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Harris said these acts of campus violence concern students.

“I’ve had messages today from students saying they want to transfer from this school and I’m telling them it’s not a good idea,” Harris said. “It’s not the school that’s the problem. It’s not the kids going to school…it’s always outside.”

The district’s letter said all players, coaches and staff at Prairie Hills Junior High are safe.

A district administrator will be available over the weekend and counseling will be available for students and staff when school resumes on Tuesday, the letter added.

Additional information was not immediately available.