LAFAYETTE, Ind. (AP) - Natural gas leaking from a line damaged by a construction crew caused explosions that destroyed four homes and injured four people, none seriously.

One adult and a child had to be rescued from the basement of one of the demolished houses.

Police evacuated residents of several blocks Wednesday, along with students and staff from an elementary school. Residents were allowed to return by evening.

Four people were treated and released at St. Elizabeth Medical Center.

Police were told Wednesday morning that a crew installing a traffic signal had hit a gas line. At least two explosions rocked the area about 20 minutes later, and two more followed over the next couple of hours.

Neighborhood resident Jessie Sewell said a gas smell permeated the area before the first explosion.

"You just don’t know how bad the gas smell was," she said. "The gas was so thick, you could see it."

Fire Chief Jim Morrow said authorities didn’t know what ignited the gas, adding, "It could have been static electricity off the carpet or answering a telephone."

Today's top stories

Growing Interest in Construction Careers Among Younger People Means Jobs Filled, Deadlines Met

Larry Young Paving Tackles Grade-Separated Interchange in Texas

Caltrans, Crews Working to Repair Highway Landslides

FIRSTGREEN Industries Launches ROCKEAT Electric Skid Steer Loader

'Tiltrotator Effect' Increases as Energy Consumption Goes Down

VIDEO: Birmingham, Ala., Awarded $14.5M Fed Grant to Revitalize Its 'Black Main Street'

Pettibone Celebrates 75th Anniversary of Cary-Lift

Fay Preps Way for Pittsburgh International Airport Modernization Project