Kanye West's ex-Julia Fox has an interesting family.

Yesterday, NYPD counterterrorism units and FDNY HazMats busted into Fox's brother and father's upscale highrise apartment on Manhattan's Upper East side.

They found a ghost-gun factory, including parts, and drug-making equipment, including pressure cookers and various chemicals.

According to the Upper East Site, it was part of a longtime investigation of Fox's brother Christopher Fox

Fox was arrested along with another man and the 30-year-old is facing charges including manufacturing a machine gun, manufacturing a dangerous instrument, weapons possession, and possession of a controlled substance.

Julia has described her brother as a "mad scientist recluse."