Emergency crews were called to the six-bedroom Port Washington home, located on Charles Avenue south of Harbor Road, shortly before 7 p.m.
Crews arrived to find the 2,200-square-foot, three-story house fully engulfed in flames, believed to be fueled by gas, according to preliminary radio traffic.
A National Grid gas crew was called in to ensure that service to the residence was disconnected.
Firefighters reported finding multiple propane tanks inside the home.
It was not immediately clear whether anyone was inside at the time, or if there were any injuries.
Drivers were warned to plan on road closures in the immediate area of Charles Avenue and New Charles Avenue by Nassau County Traffic Management.
This is a developing story. Check back to Daily Voice for updates.
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