Wearing a scarf to mask his face, the gunman held up at least three security guards and then fled the luxury Cannes hotel roughly a minute later with $136 million in diamond jewelry.
The simple, speedy theft is the biggest jewelry heist in years.
Police had previously said Sunday's theft at the Carlton Intercontinental Hotel had netted $53 million worth of treasure – even at that level, a major haul. Reached by the Associated Press, Philippe Vique, an assistant prosecutor in the Riviera town of Grasse, said the Dubai-based organizer of the diamond show had since raised the value based on a more complete inventory.
Vique described a canny, but quick and logistically simple, break-in. The suspect somehow got in through the hotel's locked French doors, which open onto Cannes's famed Croisette promenade, then held up the participants of the show with a handgun and fled on foot. The hold-up itself took about a minute, all with three private security guards, two vendors and a manager of the sale-exhibit on hand, he said.
No customers were present at the time.
"He took a bag containing a briefcase and a small box, and then fled by another French door on the inside," Vique said. "He left on foot ... it was very fast."
The bag contained rings, earrings and pendants, Vique said. As the suspect began his getaway, a few jewels spilled out of the bag of loot and were quickly recovered.
"I wouldn't say it was easily done – opening a locked door..." Vique said. "He found a way to open it. Why was he able to open this door?"
The jewelry was part of a display centering on the prestigious Leviev diamond house, which is owned by Israeli billionaire Lev Leviev. It was to run until the end of August.
A Leviev spokesman declined to comment. A day earlier, the company issued a statement saying its officials were cooperating with authorities and were relieved that no one was injured in the robbery.
The hotel, in a statement, confirmed the robbery and said none of its employees or guests "were involved in or affected by the incident." The Carlton said it was cooperating with police and would not comment further on the criminal investigation.
Jonathan Sazonoff, U.S. editor for the Museum Security Network website and an authority on high-value crime, told the AP on Sunday that police were likely to probe whether the heist was linked to recent jail escapes by alleged members of the Pink Panther jewel thief gang.
Vique said authorities were pursuing all possible leads and reviewing surveillance video footage, notably from cameras put in place by Cannes municipal authorities. But he said there was no indication so far that the suspect had links to any organized crime group.
The luxury hotel was featured prominently in Alfred Hitchcock's To Catch a Thief, starring Cary Grant as a reformed burglar chasing a jewel thief. Beyond the fiction, the Carlton has already been hit by a jewelry theft: In 1994, machine-gun-toting thieves stole $45 million in gems from the hotel – an ornate, opulent fixture of the city's most-renowned boulevard. Stars throng the hotel each year for the Cannes Film Festival, and tourists rich and middle-class alike are common.