More than 200 severely ill patients were being moved Tuesday from NYU Tisch Hospital to other areas hospital after a backup generator failed following a power outage in Manhattan Monday evening.

The outage was the result of strong winds and heavy rain from Hurricane Sandy, according to Mayor Mike Bloomberg.

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Fox 5's Brian Quinn reported from outside the medical center in Kips Bay Monday night that dozens of ambulances were loading patients to be moved to other hospitals.

The transfer of patients from the adult critical unit, neo-natal intensive unit, pediatric critical care unit and obstetrics continued Tuesday morning.

Bloomberg said that city workers were helping with the evacuation.

"Due to the severity of Hurricane Sandy and the higher than expected storm surge, we are in the process of transferring approximately 215 patients within the medical center to near by facilities," NYU Langone said in a statement. "We are having intermittent telephone access issues and for this reason the receiving hospital will notify families of their relatives arrival."

The AP reported that some of the patients are being treated for cancer. Staff and rescuers had to carry patients down the stairs because the elevators weren't working in the outage.

Patients were being moved to Memorial Sloan-Kettering Cancer Center and Mount Sinai.

Dozens of ambulances lined up around the block outside New York University Tisch Hospital as doctors and nurses began the slow process of evacuation. They started with the sickest and youngest. Some were on respirators operating on battery power.

"It's a challenging situation," NYU Medical Dean Robert Grossman told WCBS-TV. "We drill all the time for this kind of thing. But this isn't a drill. This is the real thing."

Much of New York was plunged into darkness by superstorm Sandy, a monstrous hybrid system that swept across a huge swath of the East.

Most of the power outages in lower Manhattan, where Tisch is located, were due to an explosion at an electrical substation, officials at Consolidated Edison said. It wasn't clear whether flooding or flying debris caused the explosion, said John Miksad, senior vice president for electric operations at Con Edison.

Without power, there are no elevators, meaning patients — some of whom are being treated for cancer and other serious illnesses — must be carefully carried down staircases, Grossman said.

As the patients were evacuated, gusts of wind blew their blankets. Nurses and staff huddled around the patients, some holding IVs and other equipment.

Ambulances came from around the city to help transport the sick. 

Contains reporting from the Associated Press.

Get more on Hurricane Sandy's aftermath in New York City from FOX 5 at myfoxny.com.

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