Police on Long Island are searching for four men who brazenly robbed a jewelry store with a sledgehammer in broad daylight on Saturday afternoon, police said.

The crew burst into London Jewelers at Wheatley Plaza in Greenvale around 4 p.m., a Nassau County Police spokeswoman told The Post.

They took a sledgehammer to the glass display cases and made off with an unknown number of luxury watches before they fled in a vehicle, cops said. 

Nobody was injured in the heist, police said.

The value of the stolen watches is unknown, according to police.