As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CARGO SMOKE LIGHT ILLUMINATED IN FLIGHT, CREW FOLLOWED QRH INSTRUCTIONS AND DISCHARGED NR 1 CARGO FIRE EXTINGUISHER. AIRCRAFT RETURNED TO FIELD WITHOUT INCIDENT. MAINTENANCE REPLACED BOTH FORWARD AND AFT CARGO SMOKE DETECTORS AND NR 1 CARGO FIRE BOTTLE.