Two men stole a 200-carat platinum necklace encrusted with 673 diamonds from Vienna’s Museum of Applied Arts during opening hours.

Axar.az reports, citing The Guardian, that the necklace, which once belonged to Egypt’s Queen Nazli, was smashed from a display case with a hammer.

Police have released images of the suspects and launched a search.

The necklace was worn by Queen Nazli at her daughter Fawzia’s 1939 wedding to Iran’s then crown prince Mohammad Reza Pahlavi.

It was sold by Sotheby’s in 2015 for $4.3 million.

No one was injured in the theft. The museum has temporarily closed the exhibition.