Katherine May Wilson, bottom, seen with her sister on her shoulders, disappeared in 1970 in Kirkland Lake, Ont. (Submitted by Aline Wilson)A London, Ont., man pleaded guilty in a northern Ontario court on Wednesday to the murder of a 12-year-old girl who disappeared almost 40 years ago, his lawyer said.

Barry Vincent Manion, appearing in a Haileybury, Ont., court, received a life sentence for second-degree murder with no possibility of parole for 10 years in Katherine May Wilson's 1970 disappearance in Kirkland Lake.

Her body has never been found.

The 61-year-old was arrested in January and initially charged with first-degree murder, abduction and forcible confinement.

Manion, who most recently lived in London, resided in Kirkland Lake when Katherine went missing on Oct. 10, 1970. He is a distant cousin of the missing girl, her family has said.

Before he was sentenced, the girl's sisters read emotional victim impact statements about her disappearance and how it destroyed their lives, the CBC's Jason Turnbull reported from the courthouse.

Cold case re-opened in 2006

The girl had been picking up groceries for her mother, Aline Wilson, on the afternoon she went missing on the town's outskirts. Katherine called home just before 5 p.m. to ask whether she could buy a can of pop or a bag of chips with the leftover change.

Her mother agreed, and Katherine said she was going to walk home. Katherine's two sisters walked out to meet her halfway, but the girl never showed up.

The case went cold until it was re-opened in 2006.

Manion, who has co-operated with police since his arrest, told investigators he offered the girl a ride home, but instead took her to a wooded area because he wanted to have sex with her.

Manion said Katherine refused and ran away, but he caught up with the girl. He told police he started choking her to make her stop screaming, killing her. He said he left the body in the woods.

An exhaustive police search that included dogs, helicopters and boats lasted for several weeks. Investigators say they will begin a search for Katherine's remains in the spring.

With files from the Canadian Press