STOCKTON, Calif. (AP) — Police have identified a 52-year-old man as the suspect in the stabbing death of a 15-year-old girl on a California high school campus.

The Stockton Police Department says Anthony Gray was booked into the San Joaquin County Jail for investigation of murder.

The girl was stabbed several times around 11 a.m. Monday at Stagg High School and died at a hospital. Authorities say the assailant attacked before school security and staff could stop him.

A police statement says detectives believe it was a random act and are trying to determine the motive. It was not known whether Gray had an attorney who could speak on his behalf.