Toronto police say a woman found dead in the Church Street and Wellesley Street East area was killed through neck compression, and her death has now been ruled a homicide.

Tess Richey, 22, was reported missing Saturday and found dead on Wednesday afternoon outside a building undergoing construction not far from where she was last seen, a day before what would have been her 23rd birthday.

In a news release issued Friday evening, police now say they have concluded their post-mortem examination.

"The cause of death has been determined to be neck compression. Homicide has now taken over the investigation," the release reads. 

Earlier this week, Richey's sisters told CBC Toronto that the entire family was always in close contact, and it was uncharacteristic of her not to reply to text messages.

Richey had left the home of her sister, Rachel Richey, around 11:30 p.m. on Friday for a night out with an old friend from high school.

Rachel Richey said she texted her sister Saturday morning, but when she didn't get a response she figured she was sleeping. When her texts and calls remained unanswered the next day, she grew concerned.

Tess Richey

A memorial was held in the Church and Wellesley area Thursday night not far from where Tess Richey was reported missing five days ago. (Garry Asselstine/CBC)

Tess Richey's friend, Ryley Simard, told CBC Toronto on Monday that she last saw her friend around 4 a.m. Saturday, when she decided to head home after their night out. The two had gone to Crews & Tango, a drag club on Church Street, and were very intoxicated when they left sometime after 1:30 a.m., Simard said.

The pair then met up with a man and a woman and hung out outside the woman's home on Dundonald Street for some time.

The last Simard said she saw of Richey was at 4 a.m., when Simard left the group to go home.

The Richey family's last contact with her was a notification at 3 a.m. Saturday from Tess's FitBit, and a series of Uber messages at 4 a.m. in which it appeared Richey ordered a car but never got in.

From the messages, which went to her mother's phone because it is a shared account, it was unclear whether the driver or Richey cancelled the call.

Richey's death marks Toronto's 56th homicide of the year.