CBC Toronto has learned that Ontario Provincial Police are set to update their investigation into the alleged murders of eight senior citizens in long-term care facilities in Woodstock and London, Ont.

Investigators aren't ruling out the possibility more charges could be laid against nurse Elizabeth Wettlaufer — the lone person accused in connection with the deaths.

The new details will be released Friday morning, about an hour before Wettlaufer is scheduled to appear in a Woodstock courtroom.

The OPP investigation is far from over. In fact, police have been looking into the possibility more elderly patients may have been harmed or killed. They have seized medical records of other elderly patients in long-term care facilities in southwestern Ontario who are not currently named as alleged victims in the case.

Police have also interviewed staff and nurses at at least two other nursing homes in Brantford and Paris, Ont.

CBC Toronto has learned the OPP is also investigating whether a ninth elderly patient was harmed at the Telfer Place retirement home in Paris. The woman survived what investigators suspect may have been an insulin overdose.

The patient continues to live at the home, located about 15 minutes northwest of Brantford. Wettlaufer worked at Telfer Place during the time in question.

Suspected insulin overdose

CBC News has learned the elderly woman was discovered in medical distress last spring. The patient survived as medical staff realized her blood sugar levels had apparently crashed suddenly.

In the subsequent hours and days — her blood sugar levels — which apparently had not required intense monitoring before, were checked every two hours to ensure she remained stable.  At the time, no wrongdoing was suspected.

Telfer Place in Paris, Ontario

Elizabeth Wettlaufer worked at Telfer Place in Paris, Ont. in the spring of 2016. (Reveraliving.com)

Police became aware of the situation recently after reviewing Wettlaufer's employment history and the medical records of patients she came in contact with at several long-term care facilities in southwestern Ontario. Revera Inc. owns three of those facilities in Paris, Port Dover and Woodstock.

'We will continue to follow the evidence, take it to where it leads and if warranted, lay charges as we would in any investigation.' - OPP Sergeant David Rektor

"The investigation is ongoing and at this point we are not able to comment further on any aspects of the ongoing portion of this investigation. We will continue to follow the evidence, take it to where it leads and if warranted, lay charges as we would in any investigation," the OPP said in a statement to CBC News.

Wettlaufer is currently awaiting trial, facing eight counts of first-degree murder in the deaths of elderly patients in nursing homes where she worked in Woodstock and London. Police say the patients were between 75 and 96 and died between 2007 and 2014.

Left full-time job for agencies

Wettlaufer appears to have jumped from employer to employer since leaving a full-time job at Woodstock's Caressant Care facility where seven of the patients died. By 2014 she was working for health-care staffing agencies that sent her to jobs at various long-term care facilities.

She was working in a London facility in 2014 when the last of the eight patients died. One of the agencies she worked for, Lifeguard Home Health, did not respond to questions from CBC News about her employment there.

By mid 2016, Wettlaufer was working for the St. Elizabeth health-care agency. "Elizabeth Wettlaufer worked for us part-time for six weeks in the summer of 2016. We are co-operating fully with the police investigation," agency spokesperson Madonna Galo told CBC News.

Galo would not say why Wettlaufer left the agency or if the agency had any concerns about her.

By September, Wettlaufer was seeking treatment for mental health issues at Toronto's Centre for Addiction and Mental Health. It's there that she allegedly provided information to staff that led to a police investigation.

wdr-Elizabeth Wettlaufer-Tampa

Elizabeth Wettlaufer, seen in a vacation photo on Facebook, is charged with eight counts of first-degree murder. (Bethe Wettlaufer/Facebook)

On Oct. 6, 2016, police obtained a court order preventing Wettlaufer from possessing insulin and other medications. She was also ordered not to go near nursing homes or long-term care facilities. The OPP have stated they believe the eight alleged murder victims were given lethal injections of a drug.

Statement to families

CBC News has learned police began combing through patient records at Telfer Place in November. The idea was to make sure there were no other alleged victims at any other facility that employed Wettlaufer.

Telfer Place sent out a statement to families of patients confirming that Wettlaufer had worked there between February 2015 and April 2016.  

Alison Steeves, a spokesperson for Revera Inc., Telfer's parent company, declined to answer specific questions about allegations Wettlaufer may have harmed a ninth person. Steeves referred CBC News to an updated statement that says Revera "cannot provide any further details" due to "a broader ongoing police investigation."

Two families in London, Ont., have also asked the OPP to investigate whether their loved ones — who they say died unexpectedly at a facility where Wettlaufer worked — may have also been murdered.

John Lancaster can be reached at john.lancaster@cbc.ca or at 416-205-7538.