Fire that destroyed landmark eatery was accidental, officials say

(Globe staff photo by John Bohn)

WALTHAM

The fire that destroyed Sal's Family Restaurant last Sunday was accidental, the state Department of Fire Services has said in a press release.

Investigators believe the fire started in the basement area beneath the take-out counter, probably due to an electrical problem or natural gas leak ignited by any of several sources. The damage to the site was so severe that it would be "impossible" to determine exactly what caused the spark, the release said.

The fire also destroyed a neighboring store, California Convenience.

The Waltham Fire Department, the Office of the State Fire Marshal, and Bureau of Alcohol, Tobacco and Firearms had spent most of this week combing through the charred debris by hand.

--Stephanie V. Siek