Authorities say nobody was seriously hurt by an explosion that destroyed a house in Stamford.

Stamford's director of public safety, Ted Jankowski, said the homeowner was outside the house at the time of the explosion. The homeowner was alert and conscious when emergency crews arrived and he was taken to a hospital for observation.

Mayor Michael Pavia said the cause of the blast is under investigation.

The explosion Tuesday afternoon left nothing standing of the six-bedroom, 6,000-square-foot home in north Stamford. Debris landed hundreds of feet from the house and three other homes in the neighborhood also caught fire.

Pavia said a 500-gallon propane gas tank on site was under a controlled burn.

Fire and emergency personnel from around Fairfield County and New York's Westchester County responded to the blast.

[Associated Press, ABC News]