As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE NR 1 HYDRAULIC SYSTEM FLUID QUANTITY AND PRESSURE DROPPED TO ZERO WHILE EN ROUTE. THE AIRCRAFT WAS DIVERTED TO LGW WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND THE HYDRAULIC LINE TO LT ENGINE DRIVEN HYDRAULIC PUMP CHAFED THROUGH. THE HYDRAULIC LINE WAS REMOVED AND REPLACED, LEAK AND OPERATIONAL CHECKS WERE GOOD.