As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 2665 - EWR - FLIGHT CREW REPORTED SMOKE IN CABIN AFTER T/O FOLLOWED BY LAV SMOKE INDICATION ON EICAS. CREW PERFORMED AIR RETURN AND LANDED UNEVENTFULLY. EWR MX PERFORMED ENGINE NR 1 AND NR 2 RUN UP AT HIGH POWER WITH BLEED SYSTEM ON FOR 3 MIN (TWICE). NO SMOKE NOTICED. MX ALSO PERFORMED LAV SMOKE DETECTOR OPERATIONAL CHECK SUCCESSFULLY. ACFT WAS APPROVED TO RETURN TO SERVICE.