Law enforcement officials are investigating whether the explosion that destroyed three buildings and killed two men in the East Village last week resulted from an attempt to hide the unauthorized siphoning of natural gas for tenants in one of the buildings.

Their working theory is that one or more gas lines were surreptitiously tapped over several months; then the siphoning apparatus was dismantled or hidden on Thursday before Consolidated Edison conducted an inspection. As soon as the utility inspectors left, an attempt to resume the diversion of gas went awry, setting off the explosion, according to two law enforcement sources with knowledge of this working theory.

That version of events is far from proven and is still being pieced together through interviews with utility workers and witnesses, including the owner and the manager of Sushi Park, a restaurant that occupied the ground floor of the building where the explosion took place, 121 Second Avenue, near East Seventh Street. The police interviewed the restaurant owner, Hyeonil Kim, over the weekend and heard his ideas about how gas may have been redirected to the appliances of tenants in the apartments above his restaurant.

Con Edison workers discovered in early August that a gas line for Sushi Park had been tapped to supply fuel to the tenants in that building. That siphoning, which Con Edison inspectors said had created a “hazardous situation,” was intended as a stopgap until the utility approved the use of a bigger line that could serve the whole five-story building, law enforcement sources said.