A historic diamond necklace connected to Egypt's former royal family has been stolen from a museum in Vienna after two men smashed through a glass display case in broad daylight.

The theft happened at the Museum of Applied Arts, known as the MAK, while visitors were inside. According to Austrian authorities, the two suspects entered the museum as ordinary visitors before attacking the display and escaping with the jewellery.

The stolen necklace is an extraordinary piece. It is made of platinum and contains 673 diamonds weighing more than 200 carats. The jewellery was created by French luxury house Van Cleef & Arpels and has a connection to Egyptian royalty.

The necklace was reportedly worn by Queen Nazli of Egypt in 1939 at the wedding of her daughter, Princess Fawzia, to Mohammad Reza Pahlavi, who would later become the Shah of Iran.

It was later sold at a Sotheby's auction in New York in 2015 for about $4.3 million, giving some indication of its extraordinary value.

The thieves struck during opening hours

The robbery was not carried out under the cover of darkness.

The two men reportedly bought tickets and entered the exhibition like regular visitors. Once inside, they used a hammer to smash the glass case containing the jewellery before grabbing the necklace and fleeing.

Security cameras captured images of the suspects, who were reportedly not wearing masks. Austrian police have released images as they search for the men.

No visitors or museum employees were reported injured during the incident.

The museum had been hosting an exhibition dedicated to Van Cleef & Arpels, featuring hundreds of pieces connected to the famous French jewellery house. The stolen necklace was among the historic pieces on display.

The stolen necklace at a glance

The exhibition has since been temporarily affected by the robbery as authorities investigate what happened and search for the stolen piece.

There is also concern over what could happen to the necklace if it is not recovered quickly. A piece with such a documented history would be extremely difficult to sell openly, meaning investigators will be looking closely at possible attempts to move or dismantle it.

The theft is also drawing attention because it comes amid a series of high-profile robberies targeting European museums and historic collections. Recent incidents have raised fresh questions about how vulnerable valuable cultural objects can be even when they are displayed inside major institutions.

For Austrian investigators, the immediate priority is finding the two suspects and recovering the necklace.

For the museum world, the incident is another uncomfortable reminder that some of the world's most valuable treasures can become targets even in the middle of the day, surrounded by visitors.