Two eagle-eyed cops busted a Virginia man for an illegal gun when he tried to slip into a Times Square subway station without paying, police said yesterday.

Travis Marks, 26, attempted to sneak in through the emergency gate at the 42nd street station, near Eighth Avenue, when cops spotted him at about 5:30 p.m., authorities said.

Cops said Marks then tried to dump a plastic bag with a white powder inside, which police are testing.

When the officers searched the fare-beater, they found a loaded 9mm semiautomatic handgun in his waistband.

Authorities charged Marks, who lives in Richmond, with criminal possession of a weapon, theft of service and criminal possession of a controlled substance, as well as trespassing.