EDMONTON - Criminal profilers and Edmonton police believe a single killer may be responsible for the deaths of at least seven and as many as 12 Edmonton-area prostitutes over the last 18 years, according to a police affidavit.

The document, part of an application for a wiretap, was released during proceedings against Thomas Svekla, who is charged with first-degree murder in the deaths of Rachel Quinney and Theresa Innes.

According to the 188-page document, a group of RCMP criminal profilers reviewed in 2003 the deaths of five sex-trade workers in the area around the Alberta capital.

"The committee concluded that the five murders of Edna Bernard, Debbie Lake, Melissa Munch, Monique Pitre and Katie Ballantyne were `probably committed by the same offender,''' the affidavit reads.

It goes on to say that the committee indicated the offender "will continue to frequent prostitutes and murder some of them.'''

The profilers later added the murders of Quinney and Charlene Gauld to that list.

In 2004, investigators with Project Kare concluded the murders of Corrie Ottenbreit, Delores Brower and Maggie Burke were related to the seven the profilers listed. Project Kare is an RCMP task force investigating the deaths or disappearances of dozens of people, many with high-risk lifestyles.

"The circumstances of these individual cases, combined with victimology, were such that Project Kare and I believed these victims were probably also related,'' wrote Const. Kevin Kunetzki in the affidavit.

Kunetzki himself added the 1989 death of Bernadette Ahenakew to the list. Theresa Innes -- publicly linked with Quinney through the same accused -- is the possible 12th victim.

Kunetzki emphasized that the links in the last five cases were not made by the profiling committee.

The affidavit also said that preliminary investigations suggested a 13th victim, Bonnie Jack, was "probably related'' to the other cases.

In a ruling delivered Tuesday, Justice Sterling Sanderman decided that the wiretap evidence that resulted from the affidavit will be admissible at Svekla's trial. The wiretap was conducted from August to October 2006, while Svekla was being held in the Edmonton Remand Centre.

The affidavit also hints at parts of the Crown's case against Svekla.

It details how Svekla's sister discovered Innes' naked body in his hockey bag in May 2006, after he had told his family the bag was filled with compost worms.

Police allege the 36-year-old woman was slain earlier in High Level, Alta., and that her body was transported about 700 kilometres south to Fort Saskatchewan, east of Edmonton. An autopsy revealed her remains had been wrapped in several layers of materials, including garbage bags, an air mattress, a shower curtain and wire.

The affidavit quotes several friends of Innes' saying she often associated with Svekla, but there are no reliable sightings of her in the weeks before the discovery of her body in Svekla's hockey bag. Kunetzki wrote that Innes may have been killed as early as January 2006 and her body stored in a freezer witnesses said he had in his apartment.

The freezer has not been located.

As well, about a week before Svekla told police he had found Quinney's body, he told a friend "he had done something very, very bad.''

Svekla told the woman he had to get rid of his truck. The woman also told police there was a pile of dirty clothes in the truck that Svekla would not let her near.

She also told police that Svekla had "garden-type'' scratches all over his arms that he claimed came from a cat.

Svekla was the one who reported Quinney's body to police, claiming he stumbled across the mutilated corpse while out smoking crack cocaine with another prostitute.

She was found in a patch of trees east of Edmonton, in June 2004. An autopsy revealed that her breasts and genitalia had been removed and that there were marks consistent with bruising on her legs, right forearm, neck and lower back.

Svekla is the first person to be charged by Project Kare.

Testimony is scheduled to start before a judge alone in February.