Joshua Petrin, who is serving a life-sentence in the killing of Saskatoon mother Lorry Santos, has been sentenced in an Alberta death.

Joshua Petrin, the alleged leader of Edmonton's White Boy Posse gang, was found guilty of manslaughter on Tuesday in connection with the 2012 death of Bryan Gower, according to Petrin's lawyer, Brian Pfefferle.

Charged with first-degree murder in the death of Lorry Santos, accused killer Joshua Petrin has headed to trial in Alberta on an unrelated murder charge.