Concord Police were chasing two dirt-bike riders who were driving reckless near Markham Nature Park in Concord at about 4:45 on Wednesday.
The chase began just off West Street, and ended about two minutes later. One motorcyclist drove into Markham Nature Park, and the other drove into El Monte Elementary School, which is behind Cowell Park.
Both bikes did not have license plates, and one of the riders was wearing a black hat.
The pursuit was terminated due to unsafe conditions.