Kim Kardashian has been held up at gunpoint in Paris by armed men who stole millions of dollars worth of jewellery.
A police source told Reuters that five men had robbed the reality TV star at around 3am local time.
Early reports said it had happened in a hotel, but Reuters later said it had occurred at a luxury residence.
The property, which is used by celebrities and the wealthy, is near the historic Madeleine Church.
Kardashian also stayed there before her wedding to Kanye West in 2014.
Police were seen outside on Monday.
While no-one was hurt in the robbery, Kardashian was said to have been left “badly shaken”.
The incident happened as she attended the French capital’s fashion week.
Regarding the robbery, police told the AFP news agency: “The loss amounts to several million euros, mostly jewellery.
“The total amount is still being evaluated.”
Initial reports referred to two armed men.
A spokeswoman said: “Kim Kardashian West was held up at gunpoint inside her Paris hotel room this evening by two armed masked men dressed as police officers.
“She is badly shaken but physically unharmed.”
Her husband, rapper Kanye West, cut short a concert in the US after the incident, telling fans he had “a family emergency”.
Kardashian, 35, had been photographed on Sunday evening at a Givenchy fashion show with her sister Kourtney and mother Kris Jenner, and was later reportedly seen out for dinner at a local restaurant.
West, 39, stunned fans at Meadows Festival in Queens, New York, when he abruptly ended his set during his 2008 hit Heartless.
In footage shot by fans, he is heard saying: “I’m sorry, I have a family emergency. I have to stop the show,” before walking off the stage.
The couple’s children North, three, and Saint, nine months, were not in the hotel room at the time of the incident, People magazine reported.