An accused serial killer who had pleaded guilty in the deaths of two women shocked a Winnipeg courtroom when he said Thursday he wanted to withdraw his guilty pleas for manslaughter and wished to instead go ahead with a trial.

Shawn Lamb later changed his mind and agreed with his lawyer to follow the original guilty pleas for killing Lorna Blacksmith and Carolyn Sinclair.

Thursday afternoon, a judge sentenced Lamb to 20 years, following a joint recommendation from the Crown and defence.

He’s eligible for parole in nine years, under the plea deal.

Carolyn Sinclair’s sister spoke out Thursday.

“Very disappointing knowing the fact that he's eligible for parole in nine years," said Amanda Sinclair.

Prosecutors said Lamb confessed to police in June 2012 to beating Sinclair with an axe handle and then strangling Blacksmith weeks later with a TV cord.

Court heard Thursday that both women were killed in Lamb's apartment in 2012 after they had smoked crack cocaine. Their bodies were later found wrapped in plastic and dumped in back alleys.

The families of the two women sobbed as the Crown read out the gruesome facts of the case.

The body of a third woman, Tanya Nepinak, was never found. Lamb was charged in connection to her death as well. That case remains before the courts.

Lamb has been in custody since officers arrested him in June 2012.

In a bizarre twist Thursday, as he prepared to address the court, Lamb said he rescinded his guilty plea and asked for a trial date instead.

Already overwhelmed with grief, family members of the victims watching the sentencing broke down in tears, with one man calling him a monster. Sheriffs officers escorted the man from the courtroom.

Following a lengthy discussion between his lawyer and the judge, Lamb relented and continued on with the sentencing for the original guilty pleas.

Lamb later apologized, saying he was sorry and blaming his drug addiction.

"I turn into a monster at times…I hate what I have become because of my addiction,” said Lamb.

“He is truly remorseful. Let's face it, how many people in his shoes would confess you commit two homicides? No one knows he did it and while in police custody he tells the truth,” said Martin Glazer, Lamb’s lawyer.

The family of Carolyn Sinclair doesn’t buy it.

“My sister's never going to return. Lorna's never going to return. These girls are not going to come home for Christmas. They're not going to come home for Mother's Day. They're not going to come home for any kind of holidays but he gets his three meals a day,” said Amanda Sinclair.

Court heard police gave money to Lamb for his confession in 2012, after he told them about the bodies.

"All I can say is what I said in open court today. He was paid by the police for confessing,” said Glazer.

If the case had gone to trial, there was a real concern the confession likely would have been tossed because of the payment.

The defence would not say how much Lamb received, and prosecutors had no witnesses to the crime so there was a good chance Lamb may have been acquitted if the case went to trial.

The judge has recommended Lamb serve his sentence outside of the Prairies.

- with reports from Jeff Keele, Josh Crabb and files from The Canadian Press