Thieves broke into a French cathedral early this morning and made off with priceless treasures in a brazen heist that the local bishop has called “sacreligious.”

Witnesses report that three suspects rammed into the cathedral in Oloron-Sainte-Marie in southwestern France with a tree trunk strapped to their car. Inside the church, they quickly sawed through steel bars and smashed protective glass to access silver chalices, gold objects, and other treasures from the medieval cathedral. They fled the scene in a second vehicle. 

The cathedral, which is a UNESCO world heritage site, had an alarm system, and local residents were awoken by the noise at around 2 a.m.

“I condemn in the strongest terms the attack perpetrated last night against the cathedral of Oloron-Sainte-Marie,” the French culture minister, Franck Riester, tweeted this morning. “I share the emotion of the Catholics of France who are legitimately shocked by this theft and defacement. Those responsible will be found and punished.”

Experts are assessing the damage and cataloguing the stolen loot, which a town official, Laurent Paris, says is “considerable,” according to AFP. “Over and above the monetary value, residents now find themselves cut off from their history and their heritage,” Paris says. Officials did not want to estimate the cost of the damage, telling local media that “we do not want the thieves to know exactly what they have in their hands.”

The missing items include priestly garments that were given to the local bishop by Kind François I in the 16th century, as well as gold crosses dating from the 17th and 18th centuries.

Local police are examining the CCTV footage, and forensic investigators from the nearby city of Pau have been called in to help.

In a statement, the bishop for the region of Bayonne, Lescar, and Oloron, Marc Aillet, condemned the theft as “sacreligious,” because some of the artifacts are still in use for religious ceremonies today. “I hope that the agents of this crime and the heritage that was stolen in this incident, which was fortunately well documented, are found,” Aillet says.