Nearly a year after a spectacular jewel heist in Dresden, police have detained a group of suspects in connection with the crime in Berlin.

Police conducted a series of raids yesterday, November 16, and this morning in the German capital’s Neukölln and Kreuzberg neighborhoods. Three suspects have been detained in connection with the major heist in Dresden that took place last November, when a group of thieves broke into the Green Vault museum and stole several historic items of jewelry, including 18th-century rare cut diamonds and rubies in exquisite jewel sets. At the time of the theft, the loot was estimated to be worth as much as $1 billion.

More than 1,600 officers were deployed from several German states for the operations in Berlin, which involved raids on 18 properties, including apartments, garages, and cars. According to a police statement, officers are searching for the stolen treasures and any related evidence, including computer drives, clothing, and tools.

“The traces clearly point in the direction of organized clan crime,” commented culture minister Monika Grütters. “The brute force and the highly professional approach of the perpetrators made us painfully aware of the great challenges our museums face when it comes to security.”

The public prosecutor’s office from Dresden has accused the three suspects of gang theft and two cases of arson. The suspects will face an investigating judge today.

On November 25 last year, several suspects broke into Dresden Castle’s Green Vault, one of the largest collections of Baroque treasures in Europe, through a small window. Taking advantage of what seems to have been an intentionally created power outage caused by a fire, they stole into the castle under the cover of darkness. Once inside, the thieves smashed a display case and took a group of rare jewels that once belonged to Augustus the Strong, elector of Saxony and the King of Poland. The perpetrators then took off in a getaway car, which they later torched before heading onto the highway in another vehicle.

By chance, the Green Vault’s most famous treasure, the 41-carat Dresden “Green Diamond” was on loan to the Met in New York at the time.

Police have been closing in on the suspects for some time. Back in March, police released sketches of one of the suspects, and in September, police raided a shop and a private residence in Berlin.

[3:38 CET: This article was updated to include comments from culture minister Monika Grütters.]