PORTLAND – An Auburn man has been convicted in federal court on a charge that he was in possession of weapon in violation of the National Firearms Act.

Dario Giambro, 60, was found guilty Tuesday by a jury in U.S. District Court in Portland.

According to court records, on Feb. 10, 2006, a search conducted on Giambro’s Auburn home revealed that among 204 firearms was an unregistered one.

Prosecutors said Giambro was in possession of a Marble brand Game Getter rifle, a weapon with a combination of shotgun and rifle barrels more than 12 inches but less than 18 inches in length.

Only a single discharge can be made from either barrel without manual reloading.

The unique guns were last made in the early 1900s. They’re prized by some gun collectors.

The weapon was not registered to Giambro in the National Firearms Registration and Transfer Record as required by federal law.

The search of Giambro’s home took place following in response to a shooting that occurred at Giambro’s home earlier that day.

Giambro is in jail pending sentencing.