MD-11 First Officer reported fire bells and alerts with messages stating CABIN SMOKE; CRG FIRE LWR AFT; CRG FIRE LWR FWD and all upper cargo smoke detectors indicating smoke on coast in during Ocean operations. The flight crew elected to divert and make a precautionary landing.

Narrative

Report submitted due to no cell connectivity at divert location. Coasting out over Ocean on HF at FL340 fire bells and alerts with messages stating CABIN SMOKE; CRG FIRE LWR AFT; CRG FIRE LWR FWD and all upper cargo smoke detectors indicating smoke. Turned right to head to cold bay while Captain got [Relief Officer] back to cockpit and instructed Load master to don his oxygen mask. Captain took over flying duties and delegated QRH to [Relief Officer]; and to me he delegated radios and setting up approach into new destination; and communication with [Dispatcher] on ACARS. Captain performed an emergency descent and approach while the [relief officer] and I worked the QRH and I got clearance and set up approach. FSS had emergency equipment standing by the time we arrived. I believe we were on the ground within 12-14 minutes. After the event we think electrical controller gave false fire and smoke indications - during the event we thought there was a fire in lower cargo where the only cargo was on the aircraft.