ALSTEAD — The cause of a second-alarm fire early Tuesday morning is still under investigation, but officials do not consider it suspicious, according to the town’s deputy fire chief.

The garage, which is adjacent to the two-story home at 112 Walpole Valley Road, was destroyed in the blaze, Deputy Fire Chief Mike Kercewich said Tuesday afternoon, but the house is salvageable.

“It was a good save,” Kercewich said. “They’ll be able to get quite a bit of their belongings out to work on the house.”

A family of four — parents and two children — was home at the time, Kercewich said, but no one was injured.

The fire appears to have started on the back wall of the garage, Kercewich said. The single-family home sustained water damage to the first floor, with fire damage to two second-floor rooms and smoke damage throughout much of the level.

Crews responded to the scene at 2:36 a.m. Tuesday, according to Southwestern N.H. District Fire Mutual Aid. The fire was under control between 6 and 7 a.m., Kercewich said. There was “extensive mop up,” he said, meaning responders went through the house to address any residual flare-ups in the home.

Two pickup trucks were parked outside the garage, Kercewich said, and one suffered damage to the front end and the other sustained damage to the back.

As of Tuesday afternoon, the N.H. Fire Marshal and the family’s insurance company were investigating the fire, Kercewich said.

The Acworth, Charlestown, Keene, Langdon, Surry, Walpole, North Walpole Westmoreland and Westminster, Vt., fire departments assisted at the scene, according to Mutual Aid.

Molly Bolan can be reached at 352-1234, extension 1436 or Follow her on Twitter @BolanMolly.