PD-1 responded to the area of Myrtle Ave. and Las Tunas Blvd. to assist the Monrovia Police Department and Los Angeles County Sheriff’s Department Temple Station with a stabbing on a bus that just occurred. When the aircrew arrived on scene and located a witness pointing to a church. Crew members directed units to the church to contact the witness who advised the suspect just enter the church. Crew members set a containment around the church and the suspect was located inside. The suspect was arrested for assault with a deadly weapon.