Monday’s fire at the Rumson mansion known as Blithewald appears to have been accidental, according to the Monmouth County Prosecutor’s office.

Spokesman Charlie Webster told redbankgreen on Thursday that investigators believe the fire began in a wall between a guest room and an en-suite bathroom on the second floor. But they were unable to determine if a live electrical circuit or equipment was the cause, he said.

At the time of the fire, Blithewald, on Buena Vista Avenue, was undergoing extensive redecoration for use as a designer showcase for the monthlong VNA Stately Homes by the Sea fundraiser fundraiser, which was to have begun Saturday but has now been cancelled. (Photo by John T. Ward. Click to enlarge)