A fire that broke out in Minneapolis due to an explosion of a building that contains a grocery store and several apartment units left 13 people injured, police confirmed.

Authorities who rushed to the scene are currently attempting to find out whether everyone had been able to escape from the building before it was consumed in flames.

The fire, which had been reported by no less than three alarms, started at 8:16 a.m., confirmed Chief John Fruetel of the Minneapolis Fire Department. The fire department chief added that an explosion occured first, consequently followed by the fire that broke out shortly after. By the time the firefighters and officials arrived to the scene, victims of the explosion had escaped and were outside the building while the second and third floors of the site of the explosion were engulfed in flames.

"Upon arrival crews made entry into the first floor of this structure," Chief Fruetel shared in an official statement. "Conditions became untenable very quickly, with major fires coming out of the second and third floors. Crews had to back out and go into defensive position outside of the building, applying water."

A few of the victims had been injured while escaping by jumping out of the windows of the building, officials explained to the media. The cause of the explosion remained unknown.

Chief Fruetel confirmed that the 13 victims of the fire have been rushed to the hospital for immediate treatment, including the six people who received critical injuries.

The apartment building contained nine or 10 apartments on its second and third floors, Chief Fruetel added.

"Not everybody has been accounted for in this building," the fire department chief explained. "It is possible that some are still inside."

The official temperature listing for Minneapolis today is at -1 degree Fahrenheit.