A fire that charred the entire first floor of a six-plex apartment building on the evening of Jan. 29, has displaced 12 Iowa City residents.

Rescuers responded to a call about a structure fire at 421 S. Dodge St. about 10:50 p.m.; upon arrival, officials said smoke was billowing out of the front of the building.

“As much as could be burning was burning,” said Iowa City Fire Battalion Chief Ken Brown.

University of Iowa junior Lance Iburg lived directly above the front unit, which was completely destroyed.

Iburg’s roommate Anthony Davis, 20, said nothing in their apartment was damaged, but their clothes smelled like smoke.

Officials were unable to disclose any details relating to the incident; they are calling on the public to locate a possible male witness.

An investigation regarding the source of the fire is ongoing, and it is expected to conclude today.

No residents were injured during the fire, but one Iowa City firefighter — whose name has not been disclosed — was taken to University of Iowa Hospitals and Clinics for burn injuries on his hands.

Iowa City Fire Battalion Chief Brian Platz said the firefighter was released Sunday and is “at home resting comfortably.”

Several tenants and neighbors of the building reported hearing a loud noise shortly before the building went up in flames.

“We heard some sort of a loud bang,” Iburg said. “It sounded like someone kicked in a door or something.”

A neighbor, Dominique Conway, said he heard “a big old bang like a cannon going off” and didn’t think anything of it until he saw the flames several minutes later.

Robert Corry, a civil fire investigator based in Boston, said the loud bangs could be attributed to electrical causes, pockets of fuel gas, a transformer explosion, fireworks, the explosion of aerosol cans, and potential arson.

Iburg said he ran downstairs after he heard the noise and smoke detectors going off, where he saw smoke coming from the cracks of the door of the unit directly below his. After Iburg knocked on the door several times with no response, he opened the unlocked door and his face was “hit with a cloud of smoke.”

Iburg and his two roommates told The Daily Iowan they were surprised by the extent of the damage to the building. They will live with friends or return to Williamsburg until their building can be inhabited again.

Platz said the fire caused an estimated $120,000 in structural damage and $15,000 in content damage.

Iburg said he and his roommates were relieved he purchased renter’s insurance prior to leasing the property.

Iburg’s landlord, John Faselt, declined to comment on the incident Sunday evening.

“I’m just really glad our landlord recommended renters insurance,” Iburg said. “Especially now.”