The call at 2 a.m. Wednesday was originally for a brush fire, but firefighters found the home engulfed in flames, WLAD said.
The road was partially closed through the early morning rush hour, WLAD said.
The Connecticut Post reported that the mansion, built in 1908 at 44 Castle Hill Road, was already being demolished by Wednesday morning.
The house, the former estate of the Gretsch family, was sold to the Bridgeport Diocese in 1995, the Post said. The diocese then sold it in 2013 for $1.74 million to Castle Real Estate Holdings LLC, the Post said.
It had 12,000 square feet of space with 17 main rooms, the Post said.
Click here to read the story at the WLAD website. Click here to read about the house at the Connecticut Post website.
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