Three people were arrested and more than 1,600 officers were deployed across Germany on Tuesday to search for jewellery and artwork stolen a year ago in a museum heist in Dresden.

Eighteen properties were searched in the German capital, Berlin, including 10 apartments, garages and vehicles in the hope of retrieving “stolen art treasures and possible evidence, such as storage media, items of clothing and tools,” police said in a statement.

A total of 1,638 police officers from multiple regions including Berlin and Saxony — where Dresden is located — took part. The searches were focused on the Berlin-Neukolln district.

Special forces also arrested three suspects in the morning. They are accused of serious gang theft and arson.

The large operation— which resulted in traffic restrictions across Berlin on Tuesday — comes a year after the November 25 theft of priceless 18th-century jewels from Dresden’s Gruenes Geweolbe, or Green Vault Museum.

Marion Ackermann, the General Director of the Dresden State Art Collections, said the wide-spread operation “gives us great hope that the case is about to be resolved just under a year later.”

She added that they have worked with law enforcement and a commission of experts to implement “far-reaching measures based on which we can ensure that something like this never happens again in the future,” she added.