Prime Minister Stephen Harper and Gov. Gen. David Johnston will be among the dignitaries in Lac-Megantic Saturday for a memorial mass honouring victims of the July 6 train derailment disaster.

Organizers have reserved 700 places in the 1,000-seat Ste. Agnes Church for victims’ loved ones. Remaining pew spots have been set aside for locals, volunteers and dignitaries. The service is scheduled to begin at 11 a.m.

With thousands expected to attend, two big-screen TVs will be set up outside the church to broadcast the ceremony live.

Harper, Johnston and their spouses will be joined at the service by Quebec Premier Pauline Marois and Maine Gov. Paul LePage.

This will be Harper's second visit to Lac-Megantic since the tragedy. In his first visit, he compared the devastated downtown to a "war zone."

The memorial comes a day after Quebec’s coroner’s office identified the remains of three more victims in the disaster, bringing to 34 the number of bodies identified so far.

But officials warned that their work to identify the rest has grown more complex.

It’s believed that 47 people lost their lives in the explosive derailment. Search crews have recovered 42 bodies so far and believe that five more are still buried amid the debris.

Quebec police Inspector Michel Forget said Friday investigators are now trying to identify victims based on what they were carrying with them the night of the disaster. He declined to specify what items they were looking for, out of respect for the privacy of the families, he said.

Forget also said most of the mangled and burned rail cars have been removed from the site, although two or three are still on scene. He would not say where the cars had been taken.

Meanwhile, Quebec City Mayor Regis Labeaume called on the authorities to build a new train track near Lac-Megantic so that local businesses can recover from the tragedy.

“The companies here have to make a profit and to survive they need to ship their products through railroad,” Labeaume said Friday, standing alongside Lac-Megantic Mayor Colette Roy-Laroche.

He hinted that residents would not want a train going through the city.

“A new railroad has to be built outside the city. People here will not support a train going through the city,” Labeaume said.

He also toured the red zone of the disaster and called it “the apocalypse,” saying it was bigger than he imagined.

A police criminal investigation, as well as a probe by federal transportation safety officials continues at the site. On Thursday, provincial police raided the Farnham, Que., offices of the Montreal, Maine & Atlantic Railway, the owners of the train involved in the disaster.

The federal government has promised $60 million for emergency assistance and longer-term reconstruction help for the town. It has also revamped some rules on train transport, following the advice of the federal Transportation Safety Board.

A number of lawsuits have already been launched that name the MM&A railway, company chairman Edward Burkhardt, president Robert Grindrod, and train operator Tom Harding as defendants.

With files from The Canadian Press