The death toll in the massive blaze at a seniors residence in L'Isle-Verte, Que., has risen to 24 people, with another 8 still missing, investigators confirmed Thursday.

Police say the remaining 8 victims are all located in the last 25 per cent of the ice-covered site that has yet to melt.

Investigators continued to sift through the charred ruins of Résidence du Havre, seeking clues to what caused the Jan. 23 fire, which authorities believe killed 32 people.

For the first time since fire destroyed much of the wooden, three-storey building in the town of L'Isle-Verte, 80 kilometres southwest of Rimouski on the south shore of the St. Lawrence River, media were allowed to take pictures this week of the investigators at work from a distance.

Police, firefighters and officials from the coroner's office, their breaths billowing out in temperatures of –20 C, used rakes, spades and brooms as they looked for evidence.

Some actually sat on the ground in the black debris, raising gentle clouds of ash as they used their hands to examine the remains. Police say around 75 per cent of the area has now been cleared of major debris.

Memorial service on Saturday

A commemorative Roman Catholic mass will be held at 11 a.m. Saturday at the Church of L'Isle-Verte in the town.

Prime Minister Stephen Harper is expected to attend.

The tragedy also has Pope Francis offering his spiritual support to the people of L'Isle-Verte.

A Vatican official said Thursday that Pope Francis was moved when he heard about the tragedy, and he has imparted a special blessing to those in the community.

Media coverage of Saturday's mass will be limited out of respect for the families involved, organizers said. Radio-Canada will transmit video and audio of the mass, sharing with other media.

With files from Reuters