While wanted for murder for savagely beating and stomping a 26-year-old mother to death, Isaiah Rider fled Calgary and brutally attacked three good Samaritans who had pulled over to help him after his car broke down on the side of the highway.

On Thursday, Rider admitted the facts surrounding the beating death of Christa Cachene as he pleaded guilty to manslaughter, as well as four counts of assault, and theft of a motor vehicle.

Court also heard Cachene, 26, was beaten so badly in October 2015, her own father did not recognize her when he found her body.

Originally charged with second-degree murder, Rider, 20, pleaded guilty to the lesser offence after his lawyers Balfour Der and James Wyman negotiated a plea with prosecutors Joe Mercier and Matthew Block.

What took place

According to the agreed statement of facts, Cachene had dropped her kids off with her father for the weekend of Oct. 9, 2015 and invited friends over. The group — which included Rider — partied on the Friday night and began drinking again Saturday morning.

Late that night, after two of Cachene's friends passed out on her sofa, she and Rider began to argue in the kitchen. Cachene used a small knife to stab Rider in the hand and lower back.

The fight then moved into the living room where both began punching each other. After he knocked Cachene to the ground, Rider began to stomp on her chest and head.

A friend who was upstairs heard the attack continue, finally coming to an end with Rider throwing Cachene down the stairs.

One of the party-goers witnessed the beginning of the fatal fight and went to sleep to the sounds of Cachene being attacked.

Once Cachene was at the foot of the basement stairs, Rider began to clean up her blood with bleach.

Isaiah Riel Rider, 20, pleaded guilty to manslaughter for stomping Christa Cachene to death in 2015. (Calgary Police Service)

The next morning, as Rider walked to the C-train with a friend he told her he was sorry for killing Cachene.

An autopsy found Cachene suffered numerous injuries including a broken vertebrae, broken rib and perforated liver as well as considerable damage to her spine and neck and internal bleeding. She also was found to have a brain bleed.

About two weeks later, after police had issued an Alberta-wide warrant for Rider who was wanted for Cachene's murder, he and four friends were on the side of Highway 2 after their car broke down near Ponoka.

Rider tried to flag down cars as his friends hid in a ditch. A car with two passengers and driven by Jesse Houghton, stopped to help.

Rider stopped by RCMP spike belt

As Houghton got out, Rider began beating him with a baton. His four friends emerged from the ditch, pulled the two passengers out of their car and began assaulting them.

Rider also beat the passengers with the baton. All three received serious injuries

Another driver who saw what was happening called 911, but when RCMP arrived the group fled. Rider ran into a nearby home and threatened the homeowner with the baton before fleeing in her Jeep.

RCMP caught up with the Jeep but Rider sped away. He was stopped by a spike belt and tried to run away again but was finally caught.

Court of Queen's Bench Justice Suzanne Bensler has ordered a Gladue report — a report on factors in an aboriginal offender's life that may have contributed to their criminal history — and will hear sentencing arguments on Oct. 16.

Four victim impact statements will be read at that time.