The basement was their prison.

For six weeks, two Edmonton sisters, aged six and three, were locked up in a townhouse basement with only a mattress on the floor.

Sometimes, one girl was confined inside a cardboard moving box, the lid taped shut, a rug placed on top. Both girls were often denied food and water and repeatedly beaten with belts.

Their mother, J.L., admits she disciplined the girls by making them stand in the corner while she hit them with a belt.

She didn't act alone.

Her roommate, A.M., lived in the same north-Edmonton townhouse. Her three children had beds and toys upstairs, and showed no signs of abuse.

J.L. and A.M. both pleaded guilty Tuesday to two counts of aggravated assault and one count of unlawful confinement. The two women cannot be named in order to protect the identities of the children.

An agreed statement of facts read out in Edmonton Court of Queen's Bench details the abuse inflicted upon J.L.'s daughters, and the injuries they suffered.

Babysitter rescued the girls

J.L. stopped sending her older daughter to school and both her girls to daycare on Nov. 1, 2017, because she was concerned staff would see the children's injuries and her abuse would be reported.

On Dec. 15, the mothers decided they wanted to go to a party with friends. They contacted a babysitter they had used before. A.M. picked up Justice Taylor and brought her back to their townhouse shortly before midnight. Taylor was told all the children were asleep.

Taylor heard someone knocking on the basement door. She had to shimmy a heavy dresser out of the way to open the door.

Over a period of six weeks, the sisters were repeatedly barricaded in the basement with just a mattress and no food or running water. (Court exhibit)

The two women have admitted they often used the dresser to block the door "to ensure that [the girls] could not get out of the basement and steal food."

When Taylor freed the children from the basement, they asked for food and water. Both were wearing pull-up diapers. Though the older girl was fully toilet-trained, she struggled to move because of her "significant physical injuries."

At 3:30 a.m., Taylor sent a message to the mothers about the injuries. There was no reply.

A.M. and J.L. returned home from their night of partying around 11 a.m., more than seven hours after Taylor sent her message.

When the babysitter got back to her own home, she contacted police.

Little girls' entire bodies covered in bruises

Officers arrived at the townhouse within minutes. The dresser again blocked the door. All five children were found in the basement. There was no food or drinking water.

"There was urine and feces in the basement on a cardboard moving box and the floor," according to the court document.

The girls' mom beat them with this belt, at times forcing them to stand in a corner with their hands up and pants off. (Court exhibit)

The six year old asked the constable for food and water, while the three year old grabbed him by the leg and asked to be picked up.

A paramedic examined the older girl and discovered extensive injuries. Her body was covered in bruises and there were old scars across her neck. It was later determined the deep-tissue injury to her lower back was so severe that she required plastic surgery.

A doctor determined the child's injuries were "consistent with repeated blunt force trauma to the muscle."

The three year old's front teeth were broken and required dental surgery. She had "abrasions, scabs and scarring on her face, neck, torso, arms, back, pelvis, buttocks and legs consistent with the shape of the long straight edge and buckle of a belt," according to the agreed statement of facts.

When police investigators examined the townhouse basement, they found blood from the two girls inside a cardboard box. Their DNA was also found on a belt buckle.

The abuse of the sisters ended after babysitter Justice Taylor called police. (Sam Martin/CBC)

A.M. and J.L. were arrested on Dec. 16, 2017, and have remained in custody ever since. J.L. showed little emotion in the prisoner's box on Tuesday, while A.M. wiped away tears at one point.

Justice Juliana Topolniski said the evidence in the agreed statement "amply supports" the guilty pleas.

Pre-sentence reports have been ordered for both accused.

They are expected to return to court in December for sentencing.