A judge has found Tony Gallup guilty of first-degree murder in the killing of five-year-old Jessica Koopmans.

The courtroom erupted into cheers when the verdict was delivered.

Justice Peter Martin said the evidence presented at the trial clearly proved that Gallup was the killer and was also guilty of kidnapping and attempted sexual assault.

Koopmans disappeared in Lethrbidge on May 4, 2001, on her way to a friend's house. Her body was found under a pile of brush one week later.

Gallup was arrested shortly afterwards. The 32-year-old Lethbridge man was a former friend of the family.

During the trial the court heard testimony from a psychologist who said Gallup told her he had been fighting pedophiliac urges since being abused as a child by a scout leader.

The judge said a suicide note found on Gallup when he was arrested was almost a full confession.

Before the decision came down, Jessica's mother Sylvia said a guilty verdict would mean everything to her. She said it would mean Jessica could finally rest.

The conviction carries an automatic sentence of life in prison with no chance of parole for 25 years.