A 74-year-old man was found alive inside a damaged senior living center in Washington, D.C. Monday, days after a massive blaze ripped through the facility and left him trapped in his apartment.

The man, who lived in Arthur Capper Senior Apartments in the Navy Yard neighborhood, was trapped in an apartment when officials found him Monday morning. Officials said the man, who was not identified, had a “sense of humor” and was taken out in a chair.

“We did not know he was in the building,” DC Mayor Muriel Bowser said in a news conference Monday, adding officials believe the man was a resident on the second floor.

Bowser said the man was taken to the hospital with injuries that were not life threatening. It’s unclear how he survived the five-day ordeal, though he had water bottles on his counter. Officials said he seemed to be in “incredibly good shape.”

Officials said the management company had initially confirmed everyone who lived in the building was accounted for, but acknowledged Monday that they had not seen the 74-year-old man since the Wednesday fire.

The complex was heavily damaged after it caught fire Wednesday around 3:30 p.m., prompting firefighters and about 100 Marines to rush to the scene to rescue residents, FOX5DC reported. A video captured some of the Marines sprinting toward the complex as smoke billowed out of the roof, which later collapsed.

More than half of the 160 residents displaced by the fire were relocated to King Greenleaf Recreation Center, according to FOX5DC. Officials were inspecting the building for stability and what may have caused the fire.

Four people were initially taken to the hospital for injuries that were not life threatening.