BELOIT, Wis. — Two tenants didn't know the gas line in their basement was uncapped when they installed a new gas stove, leading to an explosion that seriously injured them both and destroyed their rented home, authorities said Monday.

Emergency crews were called to the home around 7:40 p.m. Sunday. Thirty-three-year-old Tara Purdy was rescued about 20 minutes later. Rescuers pulled 37-year-old Todd Purdy out of the rubble around 9:40 p.m. Both were taken to UW-Madison Hospital. Tara Purdy was in fair condition with cuts, bruises and minor burns Monday while Todd Purdy was in critical condition with second- and third-degree burns.

A statement from the Beloit Fire Department said its investigators and the State Fire Marshal's Office determined that an open gas line in the basement contributed to the explosion. The tenants installed a new gas stove Sunday evening, and were unaware that the gas line in the basement was not capped. The basement filled with gas, and something unknown caused it to ignite, the statement said.

Diana and Roger Smith, who live across the street, heard a big boom and saw the walls blown out of their neighbor's home.

"There was a lady in there and she was saying, 'Help me, help me, I can't move my legs,'" Diana Smith said. "We kept on telling her that help was on the way."

Canned goods and other household items littered the front yard and neighboring driveways. Pieces of the house had blown onto nearby roofs.

"The walls went out and the roof came right down on top of everything," Smith said.

There were several small fires that Roger Smith was able to extinguish.

The rescues had to be approached cautiously, Fire Chief Bradley Liggett said. After securing the building, bracing was put in so the contents couldn't shift, then firefighters tunneled into the blast debris and repeated the process to rescue the residents.

"It's a tedious process because there's a lot of debris and we don't want the building to collapse any further," Liggett said.

Two pets were also inside, according to the fire department. One died and one survived.

The first police officer on the scene could smell natural gas and immediately began to evacuate nearby homes.

The house, worth about $48,500, is considered a total loss.