Suzanne Middle School in Walnut was closed Tuesday morning after a suspicious package was found, but the package was later deemed safe, authorities said.
A portion of La Puente Road was also temporarily closed between Gartel Road and Pierre Road in Walnut after what appeared to be a black suitcase was found sitting on a bench.
The scene was cleared and the road was reopened around 9 a.m. Tuesday.
Walnut High School remained open, according to the Los Angeles County Sheriff's Department's Walnut Station.
People were instructed to enter the high school using Valley Boulevard and Pierre Road, and students could be dropped off at Pierre Road south of Vejar Road, sheriffs said.
