A malfunction in a State Civil Defense siren caused the siren to unexpectedly sound near Kealakehe Elementary School shortly before 9:15 p.m. Tuesday, and Fire Department personnel were immediately dispatched to shut off the siren.
The crew reached the siren at 9:19 p.m., manually shut it down, and left the scene at 9:28 p.m., fire officials said.
The cause of the malfunction has not yet been determined, but the fire crew discovered some components of the siren system were infested with ants.
Insect infestations and geckos have caused siren failures in the past.
A maintenance crew from the Police Department radio shop was dispatched from Hilo Wednesday morning to inspect the Kealakehe siren, but the crew returned to Hilo after a fatal traffic accident in South Kona closed Highway 11.
A police radio maintenance crew is scheduled to return Thursday to inspect and make repairs to the Kealakehe siren.
Much of the equipment in the state siren warning network dates back to the 1960s. The state Legislature has appropriated $16.4 million to fund a statewide warning siren modernization effort.