BERLIN — Investigators said on Monday that 18th-century state treasures of “priceless cultural significance” have been stolen in a heist from a museum in the eastern German city of Dresden.

The interior minister of the German federal state of Saxony, Roland Wöller, called the incident an “attack on the cultural identity of all Saxons.”

Early Monday morning, at least two thieves broke into the Green Vault — one of Germany’s most well-known historic museums — breaking down shatterproof glass and specifically targeting a display case holding three sets of jewels dating from the era of Augustus the Strong, a Saxon leader during the 18th century who amassed vast amounts of treasures.

Authorities were unable to say if all parts of the targeted sets had been stolen, as they are composed of about 100 distinct elements.

A senior official for the federal state’s art collections, Marion Ackermann, said the targeted jewels were unique and impossible to replace.

Art historian Dirk Syndram described them as a “world heritage."

German authorities hope the jewels’ uniqueness would prevent the thieves from being able to sell them.

When police officers arrived at the museum around 5 a.m. on Monday, the thieves already appeared to have fled, and no suspects had been identified by Monday afternoon.

Investigators are also probing whether a power outage at a nearby square and the burning of a nearby car are connected to the heist.

The theft appears to constitute one of the biggest post-World War II thefts of cultural artifacts in Germany, even though officials hesitated on Monday to put a financial value on the targeted items.

Earlier this year, four men went on trial for allegedly stealing a massive gold coin weighing 220 pounds from Berlin’s Bode Museum in 2017. According to prosecutors, the thieves had rolled the coin away over railway tracks, using a wheelbarrow and a skateboard.

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