As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLAMES FROM THE NR 1 ENGINE WHILE TAXIING, REPORTED BY MULTIPLE PASSENGERS SITTING ON THE LEFT SIDE OF AIRCRAFT, AFT OF ENGINE. SMOKE IN CABIN WAS ALSO NOTICED. MAINTENANCE PERFORMED TROUBLESHOOTING IAW MCM 05-96-70. FOUND NO TRACE OF SMOKE, FUMES OR FIRE. THE AIRCRAFT WAS GROUNDED.