A woman places a card at a memorial for James Catholique. (Andrea Huncar/CBC)

Edmonton police are asking witnesses to a fatal beating north of downtown last week to come forward.

A passerby found James Lee Catholique, 23, of no fixed address, lying behind an abandoned building in the area of 100th Street and 107A Avenue at around 6 p.m. Thursday.

Police said he appeared to have died of blunt-force trauma suffered in a fight.

Det. Dale Johnson said officers have identified two witnesses so far, and are hoping to find a woman driving an SUV in the area at the time Catholique's body was found.

"What we know is that a male observed something significant enough that he went to the energy and effort to step into traffic and stop a lady who was driving an SUV," Johnson said. "That male attempted to have a lady call 911." The woman stopped, he said, but drove away without calling emergency services.

Police have already spoken with the male witness, but are hoping to interview the woman as they believe she has information that could help the investigation.

Alcohol addiction 'totally consumed him'

Catholique's former common-law wife, Kim Cardinal, said his death hit the family hard. Cardinal and Catholique had a two-year-old son. "I'm just going to keep all the good memories alive with my son," she said. "You know, let him know what a great guy James was and how much he did love him. But at the same time, he had this addiction, which totally consumed him. He couldn't get out of it."

Cardinal said Catholique struggled with alcoholism, but was hoping to build a relationship with his young son before his death.

"I do believe that things happen for a reason in life and I try to take the positive out of it," she said. "I guess it was meant to be. He was meant to die and I guess maybe this is what it'll take for people to stand up and take notice of what's going on — because all these homeless people are people, they do have families."

Cardinal urged anyone with information to contact police. "For his son's sake, come forward. For the family's sake, come forward and let the police know what you know, what you saw."

She said she will always remember Catholique fondly. "He's taught me so much that now … I'm trying to help people in James's situation, you know, addicts, alcoholics, and it's because of James," she said.

"It's because of James I have this patience for people. It's because of him that I've learned what I've learned. He's taught me so much in life and he's made me a much stronger woman, he really has, and I thank him for that."