Acting county Prosecutor Robert Laurino says it's not clear what sparked the shootings of 19-year-old Francisco Sierra and 28-year-old Geraldo Criado.
No arrests have been made.
Detective Hubert Henderson, a city police spokesman, said the shootings happened around 3:40 a.m. at El Nuevo Gurabo, a small social club in the city's North Ward. Both men were shot in the upper torso and were taken to University Hospital in Newark, where they were pronounced dead a short time later.
Laurino said two other people--a 13-year-old and a 21-year-old--were wounded around 7:30 a.m. in an area not far from the club.
Authorities, however, don't believe the shootings are connected.
The shooting comes just a week after Newark laid off 167 police officers from their of 1,265. This is the largest cut to the force since 1978.