The explosion and subsequent fire that destroyed a house on Academy Avenue and injured three people Tuesday morning is believed to have been caused by a natural gas leak, Albert Lea Fire Department officials said Tuesday.

Lt. Al Schallock said it appears the explosion began in the kitchen of the house, at 1421 Academy Ave.; a specific ignition source hasn’t been found.

“That’s where we’re focusing our attention,” Schallock said.

The Fire Department received the call just before 6 a.m. Tuesday. Neighbors described hearing a loud explosion, and then the house was engulfed in flames.

Four people were in the house at the time, and three were injured. Two were badly burned.

Schallock said the two were flown to Regions Hospital in St. Paul, and one man, the renter of the property, was taken to Albert Lea Medical Center. Conditions are unknown.

Steve Kurth, the owner, confirmed the tenant’s name as Rafael Ruiz.

Schallock said two were upstairs at the time of the explosion and began heading downstairs. One on the main level ran outside; the other ran upstairs and assisted the other two down.

Schallock said firefighters have one message.

“The thing we want to stress is that if you smell gas at all, get out and contact the Fire Department or call 911,” Schallock said. “We need to get people there who can figure out what type of leak is going on and take care of it.

“Leave lights alone — don’t turn on lights — and don’t do anything that could cause a spark.”