CHICAGO, Ill. (WTVO) — A Chicago firefighter died, and three others were injured, when they responded to a fire at a high-rise building.

Lieutenant Jan Tchoryk, 55, is the second Chicago Fire Department (CFD) member in two days to die in the line of duty. His cause of death is not yet known.

The fire broke out on the 27th floor of a large apartment building near Lake Shore Drive Wednesday morning. The unit did not have sprinklers.

Two civilians were also injured in the blaze.

Tchoryk was assigned to Tower Ladder 10 and served with the fire department for around 25 years.

“I can’t tell you how this impacts us, losing two members in two days,” said Chicago Fire Commissioner Annette Nance-Holt. “As I said yesterday, this job is dangerous and you never know if you are coming home, despite the best training and equipment that we can provide. Please keep his family in your prayers, as well as the entire Chicago Fire Department.”

Tchoryk served in the U.S. Navy and Operation Desert Storm. He has a son on the Chicago Police Department.

This came just one day after Firefighter Jermaine Pelt died while fighting a blaze in the city’s West Pullman neighborhood. The Chicago Medical Examiner said that Pelt died from smoke inhalation while battling the fire.

The CFD has set up an official memorial fund for Pelt’s family. He leaves behind a wife and a six-year-old son, as well as a daughter who was on her honeymoon when he was killed.