Cold Case Files: Toronto police searching for killer linked to 2 murders from 1983

Twenty-two-year-old Erin Gilmour was on the cusp of starting her adult life.

She had her own apartment in Yorkville and was just breaking into the fashion industry while working at a high-end clothing boutique.

But her life was unexpectedly cut short.

On Dec. 20, 1983, Gilmour made arrangements to attend a Christmas party.

“It was in the early evening hours, just after 9 p.m., a friend who had a prior arrangement to meet her went to her apartment to meet up and I believe they were going out that evening and they found that she was not responding to knocks at her door,” Toronto police homicide unit Det. Sgt. Stacy Gallant told Global News.

“Her door was open. When the friend went up to see where Erin was, he found her dead in her apartment.”

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The days following Gilmour’s murder revealed disturbing details on how the 22-year-old died.

“You find out as the days go by, that she had been raped and stabbed. Some of the horrific details of it all,” Erin’s brother Sean McCowan said.

“It was very hard to process. I was totally caught up in… you can’t even begin to fathom how it’s happened and why it’s happened, and who and what were the circumstances.”

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Gilmour’s killer has never been found.

WATCH: Extended Interview – Erin’s bother Sean McCowan, speaks about the days following her death.

4:12 WATCH: Extended interview with Erin Gilmour’s bother, Sean McCowan

However, the creation of a National DNA data bank in 2000 revealed her murder was connected to another homicide that happened just four months before, in August 1983.

“I think the DNA link with Susan Tice was a real eye-opener because all of a sudden you had two victims from the same guy. The (modus operandi was) the same. They were both raped (and) they were both stabbed,” McCowan said.

“There is something there that this guy picked these two woman. They were both at very different points in their life. They didn’t look similar and they lived in different areas, but there is some connection to this guy for sure.”

Police haven’t given up.

“Ultimately, to solve one of the cases means we solve both,” Gallant said.

“If we  can do that in this particular case, I think the two families would have some sort of resolve.”

Gilmour’s family has put out a $200,000 reward for information leading to the arrest of her killer.

“It’s literally just a name. If the police use the name in solving and getting to the bottom of this, then someone is going to get $200,000 and it’s price to pay for an answer to us,” McCowan said.

Anyone with information is asked to contact the police homicide unit at 416-808-7400, homicide@torontopolice.on.ca or Crime Stoppers anonymously at 1-800-222-8477.

Watch Global News at 5:30 & 6 p.m. ET Thursdays for our weekly Cold Case Files series.

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