As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW DISCOVERED SMOKE IN THE CABIN, DECLARED AN EMERGENCY AND RETURNED TO DEPARTURE AIRPORT WHERE THEY EVACUATED THE ACFT AFTER LANDING. MX DETERMINED THAT THE FWD CABIN VENTILATION BLOWER HAD FAILED AND IT'S CURRENT LIMITER AS WELL. MX REPLACED THE UNIT WITH O/H AND THE LIMITER WITH NEW, OPS CHECK SATISFACTORY.