Community activists and elected officials rallied Sunday outside Brooklyn's Interfaith Medical Center, which is in bankruptcy and slated to close.
Politicians, including Public Advocate Letitia James and City Councilwoman Laurie Cumbo, spoke at the rally, saying the community needed the facility.
On Friday, ambulances were briefly diverted from the Bedford-Stuyvesant hospital after it was revealed that it had not received all of a $3.5 million lifeline promised by the state last month, and dozens of hospital workers occupied part of the building to protest its impending closure.
The New York Times reported that the police had to be called to escort hospital chief executive Patrick Sullivan from his office.
He has already submitted his resignation, effective at the end of the month.
Another hospital official reinstated ambulance service later Friday.
Mayor Bill de Blasio made the hospital's pending closure a campaign issue and has vowed to try and save Interfaith.
A spokesman for the mayor told the Times the ambulance disruption was "disruptive and unnecessary."