The two armored vehicles owned and operated by the Secret Service were traveling together when the pedestrian was hit around 2:30 a.m. at the intersection of Suitland Parkway and Naylor Road in Temple Hills.
The SUV and limousine were not escorting anyone at the time of the accident. The cars were part of the fleet used to protect the vice president on his trip to Fort Lewis in Washington state. The cars were in the process of being returned to their garage from Andrews Air Force Base when the accident happened.
Both officers stayed on the scene and rendered first aid to the victim. The man was taken to Prince George's Hospital Center in Cheverly with multiple critical injuries, and police said he was pronounced dead a short time later.
The cause of the crash is still under investigation.
Police have not released the pedestrian's identity pending notification of next of kin.