Police say the gunmen opened fire as the victims sat helpless in their car on Old Country Road in Westbury.
Eyewitness News reporter Michelle Charlesworth has more.
Police say this was certainly an ambush and that the incident may be gang related.
All four were rushed to the hospital, each shot just after 11 p.m. while sitting in a parked car behind the Don Juan Mexican Restaurant on Old Country Road.
"They shot four guys, and one of them is dead, I think," Roberto Moreno said.
Moreno was at the scene to pick up his cousins, who called him screaming about what happened.
The young men who were shot were 17 to 21 years old, all of them targeted at close range.
Police say one of the four died early Monday morning. Two of the victims remain in critical condition. A fourth is in stable condition. They have not been identified.
The shooting happened during a specially organized "teen night" at the La Boom nightclub, which is part of the restaurant. That means no alcohol was served on a Sunday night before a day off from school.
"You'd never expect that would happen here," Moreno said.
Panicked parents couldn't believe it either, frantic on cell phones in the early hour of the morning, trying to get more information and find their children.
"Right now, all avenues are open," Nassau Detective Sergeant Anthony Repalone said. "In particular, we're going to see if any sort of gang involvement may have been a reason behind this."
Anyone with information is asked to call police.
