A group of five, all wearing masks, entered the Chopard shop at 11am on Munich's Maximilianstraße. One threatened staff and security guards with a screwdriver so the others could smash the glass cabinets with an axe and hammer, police confirmed.
They left the shop with an unknown amount of jewellery, and walked down the street, according to eyewitnesses.
Later that day police arrested seven people they believe were involved in the incident – which Munich criminal investigations chief Clemens Merkl told journalists on Thursday may have been organized by the international Pink Panther burglary gang.
Of those arrested, the Abendzeitung newspaper reported that one was a 14-year-old from Ukraine. Two others were 15 and another was a 16-year-old from Moldova.
The Pink Panther gang is thought to have 220 members spread over 20 countries. It has made hundreds of millions of euros from stealing jewellery.