New reports say that 3 people have been arrested for a possible connection to the shocking 2019 heist of jewelry and cultural artifacts from the Green Vault at the Royal Palace of Dresden.

The massive heist last November occurred after an electrical fire was set that cut power to the palace. The thieves took off with 18th-century jewelry, including the 49-carat Dresden white diamond, along with other significant artifacts. Some experts value the haul at around 1 billion euros.

A Tuesday search of 18 apartments, vehicles and other spaces in Berlin resulted in the detention of three Germans suspected of involvement in the arson and theft.

“The thieves stole cultural treasures of immeasurable worth,” Saxony interior minister Roland Wöller said after the heist. “That is, not only the material worth but also the intangible worth to the state of Saxony, which is impossible to estimate.”