Had Joseph Rubino not wrecked his car, he might still be living with a house full of guns in New Jersey.

But on the morning of July 24, Mr. Rubino was driving his white Chevy van on Route 517 in Allamuchy, N.J., when he lost control of the vehicle and slammed into a tree, seriously injuring himself and a passenger.

When officers from the New Jersey State Police began extracting Mr. Rubino from the wreckage, they noticed something unsettling in the van: a stockpile of assault weapons and ammunition. In a subsequent search of Mr. Rubino’s home, the police said they found more than a dozen other weapons, drugs and a box of neo-Nazi paraphernalia.

Mr. Rubino, 57, of Lafayette Township in Sussex County, was charged on Tuesday in federal court in Newark with unlawful possession of a firearm, along with several drug offenses.