Detectives are hunting a “lone wolf” burglar who stole bespoke jewellery and designer items worth more than £10m in a 19-minute heist at a billionaire’s row mansion in London.
The burglar broke in through a second-floor window and cracked a safe to carry out what is believed to be one of the biggest ever thefts from a British home.
He is believed to have targeted the 13-bed home in Avenue Road, St John’s Wood, on Saturday 7 December, while people were inside. The Guardian understands the man broke in at 5.11pm and spent five minutes rummaging through rooms before clambering down stairs to the first floor, where he found high-value items. He escaped through the same second-floor window at 5.30pm.
While inside he managed to break into a safe where some of the jewels were kept, with others swiped from a dressing island.
The suspect, who was armed with a weapon, was captured breaking in on security cameras, which also recorded him scouring rooms in the 22,000 sq ft (2,045 sq m) mansion. His face was covered and police and private investigators are trying to identify him.
The targeted family are offering rewards running into hundreds of thousands of pounds for the suspect’s capture and the return of the jewellery.
About eight people, including staff and some family members, were in the five-floor mansion at the time. The family do not want to be identified.
Police said the suspect escaped with £150,000 worth of Hermès Crocodile Kelly handbags, £15,000 in cash, and £10.4m of bespoke jewellery.
Among the jewels was a Graff 10.73-carat diamond ring, two butterfly diamond rings by De Beers, a Hermès 3.03-carat ring, aquamarine ring and “Niloticus Lumière” necklace, as well as numerous other items including pink sapphire earrings from Katherine Wang shaped like butterflies, police said.
CCTV shows the suspect is a white man in his late 20s to 30s, of medium build. He was wearing a dark hoodie, cargo pants and a grey baseball cap.
One source with knowledge of the investigation said the suspect’s weapon had appeared to be a small flamethrower or canister of noxious spray meant to incapacitate anyone he came across.
CCTV showed the burglar reaching for the weapon each time he heard a noise from those inside, the source said. At one point the suspect came close to bumping into a maid.
Police warned those trying to sell the stolen items that they were easily identifiable, and would not say if they believed the valuables could already be out of the country and for sale on the international hidden market.
DC Paulo Roberts, who is investigating the burglary, said: “This is a brazen offence, where the suspect has entered the property while armed with an unknown weapon and violated the sanctuary of the victims’ home.
“The suspect has stolen £10.4m worth of jewellery, much of which is sentimental and unique in its design, and therefore easily identifiable.
“We urge anyone who was in the area of Avenue Road, NW8, and saw anything suspicious to please come forward. Also, if you have seen this jewellery since, someone has offered to sell you it, or you have any further information, then please also contact the police or Crimestoppers anonymously.”
Csaba Virag, the chief of staff to the family and who was in the mansion at the time, said the video footage showed the jewel thief “had definitely done it before”. Virag said that while the actual break-in looked like it was by a “lone wolf”, turning the stolen haul into money could involve a wider network.
The family whose home was ransacked have offered a reward of up to £500,000 for information leading to the capture and conviction of the suspect. A second reward is on offer of 10% of the value of any items recovered.
Avenue Road is one of Britain’s wealthiest addresses and home to scores of largely international billionaires and millionaires.
Earlier this year, the insurers Aviva warned of a rise of over 40% in claims for high-end jewel thefts.
