An armed bandit fired a shot in the ceiling during a Bronx bank heist, terrorizing the customers inside, authorities said.

The gun-toting punk fired off one round into the ceiling as he walked into the Bank of America on Allerton Avenue near White Plains Road in Bronxwood at 10:10 a.m., cops said

The bank’s customers and employees dove to the floor for safety.

He walked up to the teller window waving his firearm in the air while demanding the teller fork over some dough, witnesses said.

“I want more money, I want more money,” demanded the thief.

The teller handed over so much cash it was spilling onto the floor, said one witness.

The money-grubber fled the scene. There are no arrests and the investigation is ongoing, police said.