The FBI and local police on Wednesday searched for bomb-making parts inside the upstate Rockland County home of a man suspected of making threats against Washington, DC, a law enforcement source told The Post.

Authorities said they were concerned the Orangetown, NY, man was in the process of acquiring the bomb parts, sources told News 4 New York.

The unidentified man, who lives in the town’s hamlet of Tappan, is believed to be a lone wolf who is not connected to any international terror groups, according to the station.

An official in Washington said the suspect didn’t have a specific target in mind.

His actions were “more of a mad at the world kind of thing,” the source told WNBC.

The man was expected to appear in federal court in White Plains later Wednesday on federal charges that have not yet been made public.

The town supervisor for Orangetown town – about 30 miles north of Manhattan — said in a statement that “there is no danger to the public.”

Orangetown police Detective Sgt. Thomas Holihan told The Journal News/lohud.com that Slocum Avenue, off Washington Street, was blocked off and residents were not permitted in or out.

He would not provide details about whether the suspect was at home.