BELLEVILLE • Police are investigating the report of a sexual assault this afternoon at Belleville East High School.

The incident was reported by school staff at about 3:10 p.m., police said. The victim and suspect know each other and are students at the school, police said.

Detectives were dispatched to Belleville East to investigate the incident, police said, and met with the alleged victim at a hospital, where she received medical treatment.

At about 5 p.m., officers took a 17-year-old male suspect into custody at a home in Shiloh.

Belleville East principal Stephanie Posey said the school sent an alert to parents shortly after the incident was reported. Posey said it occurred on campus but declined to be more specific.

"We want to protect (the victim) as much as possible," Posey said. "We take the security of our students and staff very seriously and strive to make our environment as safe as possible. We are grateful that the police responded so quickly."