(CBS) – It’s game over for fighting at sports events – that’s the message Chicago Public Schools officials want to send.

They’ve beefed up security at basketball games. On Friday, police cars were parked outside Simeon Career Academy as it played Julian.

Inside were even bigger changes. The school restricted spectators, and visitors, including media, were not allowed.

The crackdown came after 17-year-old Tyrone Lawson was shot and killed Wednesday night.

It happened following a fight at a Simeon game against Morgan Park, held at the Chicago State University campus.

Parents and students at Friday’s game say they value the extra security.

The school district says schools may make individual decisions about security at future games.