GILLETTE, Wyo. (AP) — A 22-year-old Wyoming man has been sentenced to life in prison for the first-degree murder of his girlfriend's 3-year-old boy.

Joseph Nielsen, of Gillette, was sentenced Friday by District Judge Michael "Nick" Deegan.

Nielsen maintained his innocence throughout his trial and during his sentencing when he read a prepared statement in which he accused law enforcement and prosecutors of building a false case against him.

He was convicted in September of first-degree murder and child abuse in the 2016 death of the child.

Nielsen's attorney, Nick Carter, said he plans to appeal.