As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 3916, FLIGHT ATTENDANT REPORTED SMOKE IN CABIN IMMEDIATELY AFTER PUSHBACK FROM GATE. AIRCRAFT REMOVED FROM SERVICE. FOUND NR 2 PACK BLOWING DUST & DIRT. NO EVIDENCE OF SMOKE OR OIL ODOR. REMOVED AND REPLACED THE NR 1 PACK VALVE IAW AMM 21-51-01. OPS CHECKED GOOD. AIRCRAFT RETURNED TO SERVICE.