Maunawili Elementary School was put under lockdown at around 9:30 a.m. Wednesday, according to school officials.
A lockdown was also in effect for Olomana School, according to the Department of Education.
The lockdown went into effect shortly after a siren sounded at the nearby Hawaii Youth Correctional Facility, signaling a possible escape.
School principal Ryan Amine said, "The kids are safe."
A Honolulu police helicopter was searching the area. Nearby, a crew was filming the television show "Hawaii Five-O."
School ended around 1:15 p.m. The students were escorted to their parent or guardian by staff. School staff also escorted students to the school bus while the lockdown was still in effect.
The lockdown was lifted at around 2:15 p.m.