As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SMOKE WAS REPORTED IN CABIN. RECIRCULATION AND AFT CARGO HEATER FANS WERE TURNED OFF, AND THE SMOKE DISSIPATED. THE FLIGHT LANDED WITHOUT INCIDENT. AN EMERGENCY WAS DECLARED WITH ATC, BUT THE CABIN DID NOT BRACE. REMOVED AND REPLACED CEILING LIGHTS POWER UNIT ON ROW 1A, OPS CHECK GOOD. NO SMOKE NOTED.