An MTA employee was robbed of his work keys, radio transmitter and a gas mask in Jamaica Estates Tuesday night, police sources said.

Peyton McDonald, 42, told police he was off-duty and walking near 180th Street and Hillside Avenue around 11:30 p.m. when a man approached him while holding an unknown object and demanded his bag.

The suspect ran off with his gear, which included keys, a radio and a gas mask.

Additional reporting by Gabrielle Fonrouge