The incident happened around 7:30 p.m. at 2419 Cedar Ave. in Seaford.
Officers responded to the location and found a Chevrolet work van fully engulfed in the driveway.
The fire began to spread to the house before the Wantagh Fire Department extinguished the blaze.
Officers and firefighters then checked the house for occupants, where they found an arsenal of assorted firearms and ammunition in the living room.
In total, police found 67 guns, 57 of which are considered assault weapons. More than 30 of them are "ghost guns," meaning they have no serial numbers and are untraceable. Detectives also found more than 150 high-capacity magazines and thousands of rounds of ammunition. Two silencers were also found.
The owner of the house, 62-year-old Charles Musarra, was arrested. Officials say he gave police consent to his check his home, which led to the discovery.
Musarra faces charges of first-degree criminal possession of a weapon and three counts of third-degree criminal possession of a weapon.
He pled not guilty at his arraignment on Monday.
Fortunately, no injuries were reported.
Nassau County District Attorney Anne Donnelly spoke out about the number of large guns and ammunition found in Masurra's home.
"The amount of damage, the amount of death that could come from this type of cache of weapons is truly unfathomable," Donnelly said. "In the wrong hands with the wrong people, 157 high-capacity magazines, thousands of rounds of ammunition... it could have been devastating."
The investigation is ongoing.
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