Emergency personnel tended to a fire at the Salame D'Auch Mosque in Auch, near Toulouse, Saturday. The fire destroyed three-quarters of the building, including two prayer rooms and the roof, in an incident that French President François Hollande condemned Monday as criminal arson. AFP/Getty Images

A fire that destroyed most of a mosque in southern France this past weekend was deemed arson by the French government Monday. French President François Hollande condemned the crime in an official statement released Monday, saying the actions of the perpetrators went against the "values of the [French] Republic."

The arson in the mosque in Auch, near Toulouse, occurred Saturday, just one day after a heavily armed man attacked a high-speed Thalys train traveling from Amsterdam to Paris in what authorities believe was a terrorist act. The assailant, Ayoub El Khazzani, 25, was wrestled to the ground Friday by several bystanders, including U.S. servicemen, after he boarded the train armed with a Kalashnikov assault rifle, a Luger automatic pistol and a box cutter.

Authorities have not yet identified suspects or motives in the arson incident in Auch, though authorities said they feared the crime was an anti-Muslim reaction to the Thalys attack. Anti-Muslim crimes have been on the rise in France since January, after two extremists who identified themselves as Muslim stormed the offices of the satirical weekly Charlie Hebdo in Paris, killing 12 people and wounding many more.

The French government has continued to heighten counter-terrorism strategies following the Charlie Hebdo attacks while urging citizens to differentiate between Muslims and extremists. "Muslims in France should be able to practice their religion freely and safely," Hollande said in a statement released Monday.

Prime Minister Manuel Valls joined Hollande in his condemnation of the attack on the mosque, taking to Twitter to express his disappointment. "The criminal fire at the Auch mosque is an attack against our republican values," wrote Valls in a Tweet posted from his verified account. "I condemn it with the strongest possible force," he wrote.

No one was injured in the fire that destroyed 70 percent of the building, including the roof and two prayer rooms. Firefighters who arrived on the scene Saturday said they smelled a strong odor of gasoline that later led them to rule that the fire was lit deliberately.