A power outage overnight at White Memorial Hospital in Los Angeles prompted the evacuation of more than 200 patients from a building housing neonatal intensive care and OBGYN units, according to the Los Angeles Fire Department and hospital officials.

All patients are safe, including a baby who was born after the hospital’s main, six-story building lost power during Tropical Storm Hilary and generators subsequently failed, Adventist Health White Memorial President John Raffoul said at a news conference Tuesday morning.

Doctors and nurses used flashlights to illuminate the room while the mother gave birth, Grace Hauser, a spokesperson for the hospital, said. Mother and baby were transferred to another hospital.

Los Angeles Mayor Karen Bass on Tuesday commended the LAFD and hospital staff for swiftly evacuating the patients in critical care.

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“We must get to the bottom of what happened and ensure that lives are not put at risk in this way ever again,” Bass said in a statement, noting that she once worked in the NICU at White Memorial. “A power outage risks the lives of all of those babies — and also the rest of the patients in critical care whose lives depend on respirators, ventilators and other critical life-sustaining equipment. Angelenos deserve a thorough examination of this incident.”

White Memorial first lost its main power early Monday at “the height” of the storm before its backup generators failed around 1 a.m. local time on Tuesday, Raffoul said. Hilary struck Southern California on Sunday as a tropical storm, bringing heavy rain and flooding before it weakened to a post-tropical cyclone.

LAFD responded to find 241 patients were impacted by the outage, 28 of whom were considered critical and moved to other hospitals, Los Angeles Fire Chief Kristin Crowley said at the news conference. Other patients were moved to another building on the hospital’s campus that still had power, Raffoul added.

The final noncritical patient had been moved by midday Tuesday, according to LAFD spokesperson Margaret Stewart, who said fire officials would begin the process of demobilizing.

LA City Fire Capt. Cody Weireter previously said 271 patients, 21 of them critical, were affected.

“LAFD firefighters and paramedics had to work in a coordinated effort to transport (patients) down the stairs and the stairwells to awaiting ambulances,” Weireter said in an earlier news conference.

Five of those evacuated were patients on ventilators, including two whose ventilators had just an hour left of backup battery power, according to dispatch audio recorded by Broadcastify, which captured firefighters’ efforts to coordinate the evacuation.

“We have three patients that are going to be critical, two that are on ventilators,” one firefighter is heard saying, calling for at least three engine companies. “We’re going to have to move them down manually without the elevator.”

“Copy, I’ve asked for a bunch of additional resources,” the dispatcher responded. “I understand you got one patient up there that’s the priority, and I’ll throw engines your way when they get here.”

“Affirmative,” the first responded. “Two have about an hour left on battery, and the one is immediate that would have to be moved.”

“Okay, start packing up the patient for immediate move.”

The failure of the backup generators will be investigated, Raffoul said, adding an emergency generator is being brought to the hospital in the meantime. Regular maintenance and testing are done on the trio of backup generators, he said, but he did not know when that testing had last occurred.

CNN’s Jamiel Lynch and Chris Boyette contributed to this report.

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