Arrest made in 40 year old Toronto cold case.

On Dec. 20, 1983, Erin Gilmour was found dead at her Hazelton Avenue apartment in Yorkville, ON.

She was found by her boyfriend that evening and had been sexually assaulted and stabbed .

17 years later, in 2000, DNA evidence linked Gilmour’s killing to the murder of Susan Tice.

She had been stabbed four months earlier in 1983 at a home on Grace Street, near Harbord Street, in the Bickford Park area.

Aside from the DNA evidence there was little else that linked the two cases, and both remained cold until last year.

Police announced they were investigating genetic genealogy and family tree websites, and had identified one family of interest.

Det. Sgt. Stephen Smith told CTV News Toronto, “We’re not talking 3,000, 5,000 people, but we’re talking a family unit where there’s a number of people still involved,”

Police are expected to make the announcement at a 10 a.m. Monday news conference at police headquarters.