SEATTLE (AP) — An Edmonds man who amassed an arsenal of homemade “ghost guns” despite being on federal supervision for an earlier firearms conviction has been sentenced to nearly six years in prison.

Agents found dozens of guns without serial numbers at the home of Nathan Brasfield when they searched it in February. Such weapons are called “ghost guns” because of the difficulty of tracing them.

Brasfield told U.S. District Judge Richard Jones in a letter that his depression left him susceptible to doomsday talk on the internet and he was making the guns in case society collapsed. He was sentenced Friday.