In a criminal complaint, federal authorities have charged 27-year-old Joshua Brown with possessing a machine gun.
Investigators say they say had found a MP5 firearm and an AR-15 style rifle in Brown's bedroom closet.
A FBI special agent said that in Instagram photos and messages, Brown indicated that he had manufactured a fully automatic MP5 himself.
The agent also added that Brown had several suppressors.
The FBI found and seized those items just earlier this week at Brown's apartment on Saybrook Avenue in Northeast Fresno.
He was taken into custody by the FBI on Tuesday and booked into the Fresno County Jail on a federal weapons charge.
Brown was hired by the Fresno Police Department in September 2023 as a cadet.
Officials tell Action News his employment there has since ended.
As of Thursday, Brown remains at the Fresno County Jail, where he is being held without bail.
He is due in Federal Court on Tuesday afternoon.
Following his arrest, two other Fresno Police Department employees were also placed on paid administrative leave pending an internal investigation.
Brown's defense attorney, Kevin Rooney, sent Action News a statement, writing:
Joshua Brown appeared in Court for the first time yesterday and defense counsel has not been provided with any of the evidence or investigator's reports. Do know that Mr. Brown is an honorably discharged Marine Corps Veteran who served in combat in Iraq. He has no previous criminal record at all. We are preparing for Mr. Brown's next court hearing regarding release from his current no-bail pretrial detention.
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