Thursday's pre-dawn blaze swept through the traditional wooden building at the equestrian school nestled amid the Bauges mountains in Lescheraines, eastern France. Officials have recovered eight bodies and believe all the victims are accounted for.
Originally, investigators feared nine people were killed.
Only one person, a 22-year-old instructor, escaped. She is being treated for burns that were not life-threatening, officials said. Investigators have not yet spoken to her, LCI television reported.
Authorities have not yet ruled out any possible causes of the fire, which took 45 firefighters two hours to bring under control.
``There was no doubt a stock of hay (inside), but we can't confirm anything,'' said Alain Lhuillier, deputy director of the regional fire-rescue squad. ``I haven't heard about any criminal leads.''
The school's horse stable was some distance from the dormitory that burned.
The riding school was registered with the state and affiliated with the French Federation of Equitation, Lamour said. However, the Sports Ministry said it had no control over the 12-bed dormitory.
``It's a private building. We don't have any particular documents about it,'' said town Mayor Anne-Marie Gagneur.
She added that authorities had asked for an investigation into how the center was run. The riding center offered a five-day course for $408 with room and board, according to its Web site.
The teenagers were from the area but stayed overnight at the school, authorities said.