A police source says a nurse charged in the deaths of eight nursing home residents made incriminating remarks while she was being treated for her addiction at a Toronto clinic.

The official, who spoke on condition of anonymity because of the ongoing investigation, said Wednesday that Elizabeth Tracey Mae Wettlaufer, a nurse from Woodstock, Ontario, made comments to staff at the Centre for Addiction and Mental Health in Toronto. Staff contacted Toronto police who informed their counterparts in Woodstock.

Wettlaufer, 49, was charged Tuesday with eight counts of first-degree murder in the deaths of elderly residents at two nursing homes in Woodstock, and London, Ontario in what could be one of the worst serial-killer cases in Canadian history.

Police arrested Wettlaufer on Monday. She's due back in court Nov. 2.