The victims were found at the Delta Hotels by Marriott in Woodbridge just before 2:50 a.m. Monday.
The victims were rushed to Robert Wood Johnson University Hospital in New Brunswick.
Their conditions are not yet known.
"I heard four shots, actually five, I heard running scattering all over," a hotel guest said. "I stayed here before prior, the night before and it was fine, room 125 was fine, but then last night I stayed in 227 and it was uncomfortable."
Police are interviewing witnesses who were part of a large group of people at the hotel when the violence broke out.
So far, there are no arrests.
"The safety, security, comfort and privacy of guests, staff and visitors are of paramount importance to Delta Hotels Woodbridge," Delta Hotels said in a statement. "Hotel management and staff are cooperating fully with authorities as they conduct an investigation into an on-property incident that occurred on July 12, 2021. All inquiries with respect to the matter or its investigation should be directed to local authorities."
Anyone with information or surveillance video is asked to call police at 732-643-7700 or 732-745-4060.
ALSO READ | Missing New Jersey mother found dead in Tennessee, family says
* More New Jersey news
* Send us a news tip
* Download the abc7NY app for breaking news alerts
* Follow us on YouTube