Story highlights Collision is France's worst road accident in more than 30 years

President calls it "a great tragedy"

Bus was carrying mostly elderly people on a day trip, an official says

(CNN) At least 43 people died in the fiery aftermath of a head-on collision between a bus and a flat-bed truck in southern France, in what authorities called the country's worst road accident in more than 30 years.

At least 41 of the dead were inside the charter bus, which was carrying a group of mostly elderly people on a day trip Friday to the Basque region, authorities said. But authorities were still trying to determine the identities of the victims, prosecutor Christophe Auger said, and it was possible the passenger list was lost in the fire, he said.

The driver of the truck and his 3-year-old son also were killed, Auger said.

Eight people survived the wreck on the winding, narrow two-lane highway that runs through French wine country. The bus was left a charred frame.

In a statement, President François Hollande called the accident "a great tragedy." He said the relatives of the victims could be assured of "the solidarity of the whole nation."

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