They marched against efforts to close Long Island College Hospital and Interfaith Hospital and claiming those closures will have a serious impact on health care in Brooklyn.
They've been working together, in some cases, for decades.
But Wednesday night was the last shift for some longtime nurses and staffers at Long Island College Hospital.
"Basically my services are no longer needed," said Woody Llewellyn, an ICU nurse.
They are people like ICU nurse Woody Llewellyn, who received a letter placing him on paid administrative leave.
SUNY Downstate will continue paying him to sit at home.
"This is nothing but thievery. These guys are criminal. Professional criminals!" Llewellyn said.
"I am ordering you arrested on the charge of disorderly conduct," an officer said.
Earlier, only Eyewitness News was live at the base of the Brooklyn Bridge as protestors, including City Councilman Brad Lander, were arrested protesting the pending closure of LICH, which SUNY Downstate bought in 2011, but has been trying to sell.
In a New Orleans-style funeral march across the Brooklyn Bridge that led to a rally in Foley Square, hundreds decried the impact of closing the community hospital, which is older than the bridge they took over.
"We are a vital source of healthcare in northwest Brooklyn, which has the fastest growing population in Brooklyn," said Dr. Saul Melman, Emergency Room physician.
A judge issued a restraining order banning SUNY Downstate from closing the facility, but it has drawn down its patients to practically zero.
Employees say the letters Wednesday night are a way to get them out the door, even if they continue to be paid.
But they say they are not fighting just for their jobs.
"I will not have a hard time finding a job. It's not about the job. It is about the fact that this is the only hospital in this wide swath of Brooklyn, it's about all of those tens of thousands of people that depend on this hospital and we're not letting it go," said Julie Semente, an ICU nurse.
"I'm staying until the end, until the end. Chain myself to the building, I'm not going anywhere," Llewellyn said.
SUNY Downstate, which operates the hospital, claims the unit loses 15-million dollars a month and has plans to discontinue operations.
Late last week protestors stormed the doors of the hospital trying to meet with administrators.
"Really petrified, because after 21 years where am I going to go to find a job?" worker Verona Benloss said.
While the hospital is reported to have only 11 patients being attended by staff others who receive care here are now worried.
"It's not good. It's not good for people," former patient Esther Borneo said.
Borneo's concern is that she returns to the hospital each week for care after recent spinal surgery. What happens next week?
"When you ask the doctor 'What are you doing next week?' he don't know. He says we will see what's going on. What God will do, then we will know where you are going next," she said.
The hospital has been part of the community for more than 150 years.
The real estate is probably worth a half-billion dollars, and a lot of residents are concerned the hospital land will become condos.