The fire broke out on the 27th floor of the building, located at 1212 N. Lake Shore Drive in the Gold Coast around 7 a.m. and quickly escalated.
One firefighter collapsed on the 11th floor while climbing up the stairs to the fire, and a mayday call went out at about 8 a.m. The elevators stopped working at some point that morning, CFD said.
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The firefighter's colleagues performed CPR and got him back to the lobby before he was brought to Northwestern Memorial Hospital, where he died, CFD officials and Mayor Lori Lightfoot said. He was identified as Jan Tchoryk, 55.
CFD commissioner, Mauyor Lightfoot announce death of firefighter
Tchoryk had been on the job since 1997. Just hours before his death, he had been sitting in Ladder 10's passenger seat, among the first to respond to the fire. Later, it led the procession from hospital to medical examiner's office.
"I got a text from a friend that said we had another mayday," said colleague and friend, CFD Capt. Rich Savoia. "It's just a sinking, depressing kind of sick feeling in your gut."
Tchoryk was a veteran of Desert Storm in the U.S. Navy. His son just graduated as a Chicago police officer. His backup gear still sits in his firehouse locker.
"I believe he came here because he loved it in the beginning so much, he wanted to end here," Savoia said.
Three other firefighters were injured, CFD officials said, and are in fair to serious condition. Two other people were injured, as well.
The incident comes one day after a firefighter died in the line of duty in the West Pullman neighborhood.
SEE ALSO: Chicago fire: Firefighter Jermaine Pelt dies, 2 others injured in West Pullman, CFD says
"Right now, I have two funerals to prepare for," said CFD Commissioner Nance Holt. "Two grieving families, and a huge department that is broken, including the command staff."
Procession for fallen Chicago firefighter
Flags are being flown at half-staff at the firehouse where Tchoryk was based. His family is heartbroken.
"As you might imagine, they're in shock and the grief is setting in," said Mayor Lori Lightfoot. "It's almost unimaginable."
Some residents of the building were evacuated, as firefighters put out hotspots. Other residents were told to shelter in place.
Large CFD presence at North Side high-rise; mayday called
Ryan Halpin, who lives in the building, called 911.
"My wife and I, and my 9 month old live in the building. We woke up this morning, smelled the smoke, called it in. The building reacted super-fast. They already called the fire department. They met us halfway up the stairs. They were here like that," Halpin said. "We got to the floor, went out around the back, could see flames shooting out the back of the building. We got down and saw smoke. I rounded the corner. People on the ground looking up at the building, looked up there was a jut of flames 10 feet out. I knew it was pretty big. We heard pretty quickly that they contained it to that unit."
Halpin said it was a scary situation, especially with a baby.
Part of inner Lake Shore Drive was closed while crews remained on the scene.
Large flames shoot out of North Side high-rise as CFD battles fire
The building is a condo and apartment building with over 260 units. There were no sprinklers on the 27th floor, Chicago fire officials said.
CFD struggles to cope with unprecedented loss
CFD struggling to cope with unpreceented loss
While the Chicago Fire Department is no stranger to tragedy, losing two firefighters in two days is unprecedented. Nance-Holt struggled to keep her composure at the scene.
"Let me say first pray for the families pray for the firefighters and paramedics. Because they worked on their own coworkers. They are devastated. My command staff devastated," she said. "Two days we've seen families broken, and these members will never return home to those families."
Firefighter Patrick Quane had been on the job for barely a year when his ambulance responded to a burning building in South Shore on December 22, 2010. When the roof collapsed, two firefighters were killed and 17 were injured. Processing that loss was not easy.
"For me it was the other guys. Unfortunately there is no shortage of guys that have been through line of duty deaths here on our job, and like I told some of the guys out there today. I know what they are going through. I know what they are feeling. There's just no way to describe in words how that is," Quane said.
Wednesday, as part of his responsibilities with the Chicago Firefighters Union, Quane was at the Cook County Medical Examiner's Office where Tchoryk's body was taken from Northwestern Memorial Hospital.
The somber, miles-long procession was all too familiar. He was here yesterday too, hours after Jermain Pelt died.
"We're humans. We're often times put on a pedestal of being super human and being those super heroes. And uh, we are humans and i don't think we're done processing what happened yesterday and here we are again," he said.
Lightfoot made a point of highlighting the mental health resources available to firefighters who may be struggling. The union said they are also reaching out to those who worked with both Tchoryk and Pelt.