Mason City man who traded dog for rifle sent to prison

A Mason City man who traded his dog for a .22-caliber rifle that he planned to use to kill his son was sentenced to more than 22 years in federal prison Wednesday.

U.S. District Chief Judge Linda Reade sentenced Billy Douglas Thorne, 58, as an "armed career criminal" because of six prior felony convictions for crimes including armed burglary, according to court documents. Thorne was convicted in April of possession of a firearm by a felon after a jury trial.

Thorne traded his dog, Luna, for a rifle in July 2012, according to witnesses who testified at his trial. Thorne told his ex-wife and other witnesses that he planned on using the firearm to kill his son, as well as his son's girlfriend, according to court documents.

In threatening text messages, Thorne told his son that he was coming after him, according to court documents. In one message, Thorne said: "i sold the dog, i gave her away for a shootem up."

The son reported his father's messages to the Ankeny Police Department, and Thorne was charged with first-degree harassment. Thorne's son went to Mason City with a witness who knew the rifle had been hidden in a park, according to court documents. Thorne's son turned the gun over to police.

Thorne will be in the custody of the U.S. Marshals until he can be transferred to prison, according to a news release. Additionally, he'll serve a five-year supervised release term after he leaves prison.