France ? A bus carrying Polish Catholic pilgrims from a holy site in the French Alps plunged off a steep mountain road, crashed into a river bank and burst into flames Sunday, killing 26 people, authorities said.

Fourteen others were seriously injured in the wreck on a dangerous stretch of road where past bus accidents have killed dozens of people. Firefighters said the bus did not have the special permit required to use the 12 percent gradient road.

Polish President Lech Kaczynski and his French counterpart Nicolas Sarkozy traveled to Grenoble late Sunday to meet with the injured. Sarkozy said he was “shattered by the scale of the tragedy” and pledged to follow “very closely” the investigation into the causes of the accident.

Local residents said the bus missed a 90-degree bend in the steep mountain road near the village of Vizille as it returned from the shrine of Notre-Dame-de-la-Salette. The bus plowed through a barrier and plunged 65 feet onto the banks of the La Romanche River, catching fire on impact, firefighters said.