Officials continued investigations into how an 87-year-old resident of a government-run Mississauga, Ontario, nursing home was unaccounted for and trapped in the elevator for more than 24 hours during the Christmas holiday.

Carolyn Clubine, director of long-term care for the Region of Peel, said the region is “reviewing and tightening” sign-in procedures.

“We will make all the corrections necessary to fulfill our responsibility,” she said.  Region of Peel chair Emil Kolb said residents and their family members are being required to sign in and out of the Malton Village Long Term Care Centre.

The woman, who was identified as Rosalie Rowsell, returned to the facility after dinner with her family on the evening of Dec. 23. She was found at approximately 2 a.m. on Dec. 25 in the malfunctioning elevator, which had been shut down the morning before.

Kolb said in a statement Wednesday that staff thought the woman had stayed with family when she didn’t return to her room. Clubine said it wasn’t discovered that Rowsell was missing until the nursing home staff called her family to check on her Christmas Eve.

After searches of the nursing home by staff and the local police were unsuccessful, the staff checked the elevator, “the only place left to search,” Kolb said.

Rowsell was taken to the hospital “as a precaution for mild dehydration,” according to Peel Region police media relations officer Const. Thomas Ruttan.  She was back at the nursing home by dinnertime Christmas Day and reportedly declined to discuss the incident with members of the media, considering the matter to be “over.”