Four southern California schools were placed on lockdown Thursday after two assault suspects on the loose were spotted in the area, according to FOX affiliate KTTV-TV in Los Angeles.

Los Angeles County sheriffs told FOX News they were serving a search warrant on robbery and assault charges when the suspects, a male and a female, ran away. The pair may be armed, they said, and a police manhunt was under way.

Officials put Los Altos High School in Hacienda Heights, about 18 miles east of L.A., on lockdown, as well as Qwis Elementary, Shady Bend Elementary and Newton Middle schools.

The suspects were not believed to be students at any of the schools.