The remains of James Hook & Co., destroyed in an early morning blaze last month.

Arson did not the spark the fire that gutted the James Hook & Co. building last month, and investigators identified the likely cause as an electrical or mechanical problem.

“It’s not suspicious,” said one official close to the investigation
The early morning blaze at the waterfront landmark at 440 Atlantic Ave. in Boston caused $5 million in damage, including the loss of 60,000 pounds of lobster. The Hook family, operators of the company since 1925, has vowed to rebuild.

“I’m relieved that arson has been ruled out, but I’d like to know what caused it,” James Hook told Banker & Tradesman on Wednesday. “I knew it wasn’t arson, but they had to investigate it as a technicality. I mean, who would they look at as a possible arsonist?”

The investigation has been delayed by the discovery of asbestos on the pipes, the source added. The hazardous materials caused investigators to stop to make way for an environmental cleaning company.

Since the fire, the family has set up temporary retail quarters in a trailer near the burned building. The company’s wholesale operation is located in the city’s Marine Indus-trial Park. A competitor, P.J. Lobster, stepped in to help with offers of lobster tanks.