As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED. FLIGHT DIVERTED. EMERGENCY DECLARED. AT APPROXIMATELY 3 HOURS AND 35 MINUTES INTO FLIGHT NR 1 ENGINE OIL QUANTITY SHOWED 0 FOLLOWED BY DECREASING OIL PRESSURE. ENGINEERING REPORTED BORESCOPE OF THE COMPRESSOR REAR FRAME INDICATED COKING BUT WAS UNABLE TO CONFIRM SOURCE.