Donna Parkinson testified Monday she found a body in a bag belonging to her brother, Thomas Svekla. ((CBC))

Thomas Svekla's sister testified in a shaking voice Monday about the day she opened a hockey bag her brother had left in her Fort Saskatchewan home and found the body of a woman, tightly wrapped in plastic.

Donna Parkinson, one of the Crown's key witnesses at Svekla's double murder trial in Edmonton, told the court she didn't believe her brother when he said the bag contained $800 worth of compost worms.

"We opened the bag right up," she said. "We stood there and looked. I squeezed and said it's too hard, that's not compost worms."

Parkinson said she could make out the outline of a head, back, arms and feet. She called the RCMP and her brother was arrested the next day.

The body was that of Theresa Innes, 36, one of the two women Svekla is charged with killing.

Svekla has said he did not kill Innes, but was transporting the body back from High Level so she could be buried.

He also faces second-degree murder charges in the death of Rachel Quinney, 19, whose body was found in a wooded area east of Edmonton in June 2004.

Svekla's sister testified she had become suspicious about her brother's actions around the time Quinney's body was found.

Parkinson said Svekla showed up at her home and said, "I did something really bad. I did a bad thing. You're going to hate me. People are going to hate me."

She said her brother refused to tell her what he'd done, but he was covered with fresh scratches.

"Like it was one hell of a mean cat. His arms were scratched to hell," she said.

A week later, she said, the young prostitute's body was found.

Earlier in the day, the court heard from a prostitute who was with Svekla the day he discovered Rachel Quinney's body.

Shannon Millward said they had been smoking crack cocaine for several hours, before driving to a secluded area east of Edmonton.

Svekla stumbled over the body when he got out of the truck to relieve himself, she testified.

Millward said he was "distraught and panicky," but did not want to call the police for fear he would be blamed.