Suspect Arrested for Manufacturing Weapons 

December 17, 2025 – Riverside County Sheriff’s Office officials report that on December 13, 2025, at 3:30 p.m., deputies assigned to the Jurupa Valley Sheriff’s Station Special Enforcement and Problem-Oriented Policing Teams received information that a subject was using a controlled substance and manufacturing illegal firearms at a residence located in the 5000 block of Steve Street in the city of Jurupa Valley.

During the investigation, deputies obtained a search warrant, and the following items were located and seized: 13 firearms, two of which had been reported stolen and one short-barreled rifle; 20 3D-printed lower receivers; numerous suppressors and large-capacity magazines; hundreds of rounds of ammunition; a small quantity of methamphetamine and drug paraphernalia.

The suspect, identified as Marco Ponce de Leon, a 37-year-old resident of Jurupa Valley, was arrested and booked into the Robert Presley Detention Center for the following charges: a convicted felon in possession of a firearm and ammunition, possession of an assault weapon, manufacturing an assault weapon, manufacturing unserialized firearms, and multiple additional weapon-related charges and drug charges.

This is an ongoing investigation, and no further details are available. Anyone with information on this investigation can contact Deputy Alexis Sanchez of the Jurupa Valley Sheriff’s Station at (951) 955-2600.

The Jurupa Valley Sheriff’s Station is committed to serving the members of our community and keeping our neighborhoods safe. Community Safety is a shared responsibility, and we encourage our members to report any suspicious activity to law enforcement. By working together, we can prevent crime and help ensure a safer community for all. If you see something, say something.

Reporting Supervisor: Lieutenant Santos Cortez

File # JV253470067

Source & photo: Riverside County Sheriff’s Office