Anaesthetic gas may have been used against Jenson Button and his wife Jessica during a burglary in France, the Formula 1 driver’s spokesman says.
Two men, who stole jewellery including Jessica’s engagement ring, may have pumped gas through the air conditioning before Monday’s break-in, he said.
The couple were with friends in a rented villa in Saint-Tropez.
The British former F1 champion’s spokesman said they were unharmed but everyone was “unsurprisingly shaken”.
The Sun newspaper reported that valuables worth £300,000 were stolen.
The couple married in December.
Button’s spokesman said: “Two men broke into the property whilst they all slept and stole a number of items of jewellery including, most upsettingly, Jessica’s engagement ring.
“The police have indicated that this has become a growing problem in the region with perpetrators going so far as to gas their proposed victims through the air conditioning units before breaking in.”
Button, 35, who drives for team McLaren, is based in Monaco, about 80 miles (130km) along the coast from Saint-Tropez. He won the F1 championship in 2009 driving for Brawn GP and finished in eighth place in 2014.
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