DENVER (AP/CBS4) – A Colorado man accused of trying to trade pipe bombs and hand grenades for drugs or cash has pleaded guilty to two counts of possessing firearms that weren’t registered with a national database.

Richard Lawrence Sandberg, 35, of Morrison, pleaded guilty late last week to two counts of possession of firearms, including destructive devices.

CBS4 Investigator Rick Sallinger covered the incident earlier this year when bomb disposal teams descended on a Jefferson County neighborhood.

Federal prosecutors said Monday that Sandberg could receive prison time and fines at a sentencing hearing scheduled Sept. 25.

According to his plea agreement, Sandberg was arrested Jan. 24 after showing the explosive devices to an undercover detective who was introduced to Sandberg through a confidential informant.

Agents said Sandberg claimed to be a demolition expert who was paid large sums of money to build bombs and kill people. Sallinger found out many of his boasts were not true. On his door was a Marine reconnaissance battalion decal, but his military record showed he only served in the reserves before leaving the service.

Court documents say a search of Sandberg’s home turned up 28 more homemade destructive devices, several hundred rounds of ammunition, and three firearms.

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