HONOLULU (AP) — Civil defense sirens that sounded across Oahu even though there was no emergency were inadvertently activated from Nebraska.

Hawaii Civil Defense spokeswoman Kelly Kunishige (COO’-nee-SHE’-gay) says eight sirens accidentally went off early Thursday because of an engineer doing upgrade work in Nebraska.

Illinois-based Federal Signal has been contracted to do modernization work for Hawaii’s more than 300 sirens across the islands. The state asked the contractor to do some checks, but after doing so, Hawaii’s siren protocols were not removed from the system, allowing some to be activated.

Kunishige says the project will allow sirens to be activated by satellite or cell phone in case radios are down.

The sirens are used during emergencies such as tsunamis.

Tsunami waves struck Hawaii in the aftermath of Japan’s earthquake last year.