B767 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 184; Flight Crew Total 31000; Flight Crew Type 10876
Other / Unknown
Conflict Airborne Conflict
General None Reported / Taken
Environment - Non Weather Related
After arriving at the gate; an Air Marshal informed me he saw a drone just off the left wingtip on short final to [Runway] 4R EWR.   It was close enough for him to see the propeller blades on the drone. He observed it abeam the oil refinery on short final to [Runway] 4R and gave me [an approximate] time. I would say it was inside 1;000 feet altitude. None of the pilots saw a drone; but I decided to report this as the Air Marshal is a reliable source. I notified one of our pilot reps in the EWR Ramp Tower; and was given the phone number to call EWR Control Tower to inform them. The drone did not hit the aircraft.
B767 Captain reported a UAV; observed by a sky marshal from the passenger cabin; less than 1;000 feet horizontal.