EDMONDS, Wash. — Authorities say a Washington state man who went to prison on a gun charge amassed an arsenal of homemade “ghost guns” after his release even though he was on federal supervision. 

Nathan Brasfield, of Edmonds, began a three-year term of supervised release in October 2017.

The U.S. Attorney's Office in Seattle said in a federal complaint unsealed Thursday that when agents searched his home and vehicle on Feb. 6 they found dozens of guns as well as several machines used in the home manufacturing of firearms. 

Brasfield's attorney declined to comment. 

Ghost guns are any guns that do not have serial numbers, such as those created using 3-D printers. The unregistered guns can be made without a person undergoing a background check.

The guns are often not picked up by metal detectors. 

Some federal law enforcement authorities worry the plastic guns could become a national security threat as the technology to make them becomes more advanced. 

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