Santa Rosa police arrested a Windsor man Thursday following a monthlong investigation into the manufacture and sale of illegal firearms without serial numbers.

Detectives with the Santa Rosa Police Department’s Property Crimes team believe 32-year-old Fredy Oseguera was using a 3D printer to create the components for assembling handguns and assault rifles he was then selling in Santa Rosa and the surrounding area, according to a department news release.

Such weapons are often called “ghost guns” by law enforcement officials.

In June, detectives began investigating a person they believed to be illegally manufacturing and selling firearms throughout the greater Santa Rosa area. They identified Oseguera as a suspect, and officers detained him outside his Windsor home at 4:15 p.m. Thursday, according to the release.

Detectives then searched two homes connected to him, a home in the 9200 block of Windsor Road in Windsor and another in the 3400 block of Santa Rosa Avenue in unincorporated Santa Rosa.

A search of the properties turned up five firearms, magazines, ammunition, 19 partially manufactured handguns and eight partially manufactured rifles, a handgun silencer and a device to convert semi-automatic Glock handguns into automatic weapons, according to police.

Oseguera was arrested and booked into Sonoma County Jail suspected of seven felony offenses related to the possession, manufacturing and sale of firearms. He was also arrested on felony child endangerment, after police found a 10-year-old boy in Oseguera’s house with access to unsecured firearms and loaded magazines, according to police.

Oseguera’s 31-year-old girlfriend was also arrested on child endangerment charges, according to police.

Detectives are working to try to connect weapons they accuse Oseguera of manufacturing to area crimes and previously seized illegally manufactured weapons, according to police spokesperson Sgt. Chris Mahurin.

Staff Writer Kathleen Coates contributed to this story. You can reach Staff Writer Andrew Graham at 707-526-8667 or andrew.graham@pressdemocrat.com. On Twitter @AndrewGraham88

Business enterprise and investigations, The Press Democrat 

I dig into businesses, utility companies and nonprofits to learn how their actions, or inactions, impact the lives of North Bay residents. I’m looking to dive deep into public utilities, labor struggles and real estate deals. I try to approach my work with the journalism axioms of giving voice to the voiceless, comforting the afflicted and afflicting the comfortable in mind.

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