As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RETURNED TO FIELD DUE TO NR 1 ENGINE COMPRESSOR STALL. CAUSE OF STALL WAS FOUND TO BE LIBERATED SECTION OF HIGH PRESSURE COMPRESSOR (HPC) 5TH STAGE BLADE. LIBERATION CAUSED DOWNSTREAM DAMAGE, INCREASED TIP CLEARANCE, AND REDUCED SURGE MARGIN OF HPC TO STALL POINT.