Investigators say he was hit by as many as two vehicles and pronounced dead at the scene.
Eyewitness News has learned he was an MTA subcontractor, employed by Summit Security.
One driver, 65-year-old Harley Greenfield, stayed at the scene. He refused to take a breathalyzer exam, authorities say.
He was charged with driving while impaired and more charges could be added.
A second driver is believed to have left the scene.
The crash was witnessed by an MTA bus driver on the QM2A line. Officials say he called for help, but the guard could not be saved.
