The mother of an Edmonton teenager stabbed through the heart at a party tried to speak through her tears as she took the stand as the first witness at the trial of the 19-year-old charged with her son's killing.

The teenager, who cannot be identified under the Youth Criminal Justice Act, pleaded not guilty Monday in Edmonton to a charge of second-degree murder in the death of Joshua Hunt.

Hunt, 16, was stabbed at a house party in October 2006.

The accused, who was 17 when Hunt died, has elected to be tried by judge alone.

Julie Hunt tried to hold back tears as she told the judge how two of her son's friends came to the door at 3 a.m. to tell her Joshua had been stabbed and was in hospital.

While she was on the way to the hospital, Hunt told herself, "He's seriously injured. We'll get through this."

However, she soon found out her son had died. She told the judge what happened when she went to see him.

"He was laying on the stretcher," Hunt testified. "They wouldn't let me touch him. I just wanted to touch him. I just kind of collapsed."

In his opening statement Monday, Crown prosecutor Christian Lim alleged the accused slashed two other young people at the party before stabbing Hunt through the heart.

Lim told the court Hunt was drunk, took ecstasy and passed out on a bare mattress in the basement of the accused's house.

Hunt was friends with the brother of the accused, and had shown up at the house with a number of other young people.

According to the Crown, the accused came home drunk, and became angry about the teens being in his room.

In the ensuing scuffle, the accused was kicked in the head. He ran upstairs, grabbed a knife, and tried to lock the teens in the basement and called 9-1-1, Lim told the court.

One teen, who got out of the basement by climbing through a window, began throwing rocks at the house, diverting the accused's attention.

The basement door was open, and when Joshua Hunt came up the stairs, Lim said he was stabbed through the heart by the accused.

The accused is also charged with two counts of assault with a weapon.

With files from Janice Johnston