Suffolk police investigate a robbery by a man with a...

Suffolk police investigate a robbery by a man with a knife at a Lake Grove Dunkin' Donuts on Friday, Dec. 22, 2017. Credit: Stringer News Service

A man with a knife robbed a Dunkin’ Donuts in Suffolk on Friday night, Suffolk police said.

He demanded cash about 7:40 p.m. from employees at the Lake Grove store on Middle Country Road, then ran off with the money, police said.

Fourth Precinct detectives are investigating, police said.

No other details were released.

On the latest episode of "Sarra Sounds Off," Newsday's Gregg Sarra and Matt Lindsay take a look top boys and girls basketball players on Long Island. Credit: Newsday

Sarra Sounds Off, Ep. 15: LI's top basketball players On the latest episode of "Sarra Sounds Off," Newsday's Gregg Sarra and Matt Lindsay take a look top boys and girls basketball players on Long Island.

On the latest episode of "Sarra Sounds Off," Newsday's Gregg Sarra and Matt Lindsay take a look top boys and girls basketball players on Long Island. Credit: Newsday

Sarra Sounds Off, Ep. 15: LI's top basketball players On the latest episode of "Sarra Sounds Off," Newsday's Gregg Sarra and Matt Lindsay take a look top boys and girls basketball players on Long Island.

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