An ex-girlfriend of an accused killer took the stand in an Edmonton courtroom Friday. The woman admitted telling people she wanted her boyfriend's mother dead, but insisted she never told the accused to kill his own mother.

In a videotaped interview shown at the first-degree-murder trial for Keshroy Bristol, the jury heard the young man tell police his ex-girlfriend asked him if he wanted to kill his mother, Beverly Parker. And he said she had put forward the idea of strangling the woman to death.

Delmy Vega-Medrano told the jury she didn't get along with Bristol's mother.

Vega-Medrano admitted she told her ex-boyfriend that she wanted his mother dead. She told the court she disliked the woman because she was attempting to adopt the baby daughter she had with Bristol.

And when defence lawyer Rob Shaigec asked the woman if she was involved in the killing or if she supplied the rope that was used to strangle Parker, she answered "no".

She also denied that she felt threatened by Parker's attempts to adopt her child. But Shaigec read out what she had told police shortly after the killing.

"I wanted to kill her sometimes. I'm not even joking. I'm dead serious."

And when asked if the statement was correct, Vega-Medrano responded, "yes".

Earlier in the week, jurors heard Bristol confess to strangling his mother to death back in February of last year in the videotaped interview with a police detective.

"I did not kill my mother," Bristol said.

The officer questions how the young man could have seen his mother lying face down outside their home, through a foggy door and not bother to go out to help.

"You didn't call out to her," the detective said. "You didn't do anything because you already knew she was dead."

"I'm sorry I didn't jump outside and go to her. I didn't do that. I just froze," Bristol told the detective.

Four hours after the interview began, another officer comes in and the questioning becomes more aggressive.

"You hit her?" said the detective. "I hit her and I just started strangling her and she fell on the spot where she landed," Bristol replied.

"What did you use to strangle her?" the detective asked. "A rope," said Bristol.

The young man then tells the detective, officers would find the rope he used hidden in a couch, along with rubber gloves in a VCR and dark clothing in the basement.

With files from CTV's David Ewasuk