Petros Krommidas, 29, has been missing since Wednesday.
Nassau police say he was last seen in Baldwin around 9 p.m.
Krommidas is described as 6'2", 230 pounds, with brown hair and brown eyes.
He was last seen wearing a camouflage print sweatshirt and gray sweatpants.
Police say Krommidas is believed to be in the Long Beach area.
Anyone with information on his whereabouts is asked to contact the Nassau County Police Department Missing Persons Squad at (516) 573-7347, or to call 911.
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