As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ATB: FL 350 SMOOTH AIR LT ENGINE EXPERIENCED LOUD BANG, MODERATE VIBRATION AND LOUD GRINDING SOUNDS. SHUT DOWN ENGINE AND RETURNED TO OGG. INITIAL FINDINGS DURING LT ENG HPC BORESCOPE. FOUND 5TH AND 6TH STAGE COMPRESSOR BLADES AND STATOR DAMAGED. LT ENGINE WAS REMOVED & REPLACED.