Two women were shot, one fatally, just after midnight Saturday in Hempstead, Nassau police said.
The "ShotSpotter" system had alerted the police of multiple gunshots and officers responded to Martin Luther King Drive, police said.
One victim, who was 28, was pronounced dead at a local hospital, police said.
The other woman, 29, is in stable condition, the police statement said.
Anyone who could help investigators should call Crime Stoppers at 1-800-244-TIPS or 911. All callers will remain anonymous.