PITTSBURG — A 27-year-old man suspected of illegally making and selling guns, including assault weapons, was arrested, the Contra Costa County Sheriff’s Office said.

The law enforcement agency said they will be testing the weapons to see if they are linked to any crime or shooting.

The suspect, identified as Diego Vasquez-Gomez, was arrested on Thursday (Jan 2.) when detectives from the Contra Costa County Sheriff’s Office served a search warrant at a residence in Pittsburg. This was part of an ongoing investigation into a shooting at the Contra Costa Fairground in Antioch last September.

The shooting stemmed from an argument in which two suspects opened fire, resulting in a man suffering life-threatening injuries.

Detectives said one of the two suspects had used an illegally manufactured gun during the shooting.

During the search at Vasquez-Gomez’s home, authorities found assault weapons and a short-barrel rifle. Some of the weapons seized did not have serial numbers.

“The weapons will be tested to see if they are linked to any shooting or crimes,” said the Contra Costa County Sheriff’s Office in a news release.

Vasquez-Gomez was booked into the Martinez Detention Facility on charges including manufacturing a short barrel gun, manufacturing and selling of an assault weapon, illegal possession of an assault weapon, unlicensed transfer of a firearm and child endangerment.

Those with information on the case are urged to contact the Investigation Division at (925) 313- 2600, email them at tips@so.cccounty.us, or call (866) 846-3592 to leave an anonymous voice message.