Three crooks robbed an on-duty state parole officer in the Bronx this week — snatching his service weapon from its holster, authorities said. 

The officer was on Leland Avenue near Archer Street in Van Nest around 5:45 a.m. Monday when the trio approached him, cops said.

They ordered him not to move and grabbed the gun, as well as his cellphone, police said. 

The suspects, captured in video released by cops late Tuesday, remain at large. 

They are shown descending a staircase and leaving a building.