Marguerite Lanthier/Daily News Three people were injured — two critically — after a fire broke out Sunday morning at 411 Fourth St. in Iron Mountain, the Iron Mountain Fire Department reported.

IRON MOUNTAIN — Three people were injured — two critically — in a fire Sunday morning at 411 Fourth St. in Iron Mountain.

A structure fire with possible entrapment was reported at 7:38 a.m. (CST), with two occupants able to get out of the structure before the Iron Mountain Fire Department arrived, said Jeff Solka, director of police and fire services. A search of the building located an unresponsive person and IMFD personnel started resuscitation efforts before the patient was transferred to Integrity Care EMS.

All three adults were taken to Marshfield Medical Center-Dickinson, with two of the patients transferred to another facility, Solka said Monday in a news release.

“The last update received was these two patients were stable, but are in critical condition,” he said, adding the cause of the fire remains under investigation.

Crews had arrived in under four minutes of dispatch to find heavy smoke and fire showing from the front and two sides of the structure, Solka said. One crew made entry into the first floor and a second crew entered the back side of the building, where the unresponsive person was found.

Breitung Township Fire Department assisted IMFD in suppressing the fire, Solka said.

The crews overhauled the first floor, second floor and the attic of the structure to ensure no fire conditions remained, he added.

Also at the fire were Iron Mountain Police, Iron Mountain Department of Public Works, DTE, We Energies, Dickinson County Sheriff’s Department and Integrity Care EMS.

IMFD responded initially with an engine and four firefighters. A recall of off-duty personnel brought in another five firefighters, an engine, aerial and a utility pickup.