A 911 call reporting the burglary at the popular restaurant was received early Monday morning, according to police.

Nassau County police detectives are investigating a burglary Monday at the iconic Massapequa eatery All American Hamburger Drive-In.

A 911 call reporting the burglary at the restaurant on Merrick Road was received at 4 a.m., according to police.

On Monday afternoon, All American Burger was bustling with customers, hours after burglars broke windows to enter the restaurant before dawn.

A back window was broken but entry was restricted by steel bars, said manager Rich Vultaggio. The intruder broke a side window and jumped the counter to steal an unknown sum of cash, Vultaggio said.

The store has reopened and is working closely with Nassau County police, including through surveillance video footage, he said.

Police said a man was seen at the scene wearing a black T-shirt, camouflage shorts and a red face covering. 

Photo of the suspect accused of breaking into the All...

Photo of the suspect accused of breaking into the All American Burger restaurant in Massapequa on Monday.

All American has been a South Shore staple since opening in 1963, noting on its website: "ALL of our recipes remain original in order to provide you with the very best."

Newsday's John Asbury contributed to this story.

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