PARIS — A lone man wearing gloves, a cap, and a scarf to mask his face sneaked into a diamond show in a luxury Cannes hotel and made off with some $136 million of loot, a French state prosecutor said Monday — more than twice the initial estimated take from the weekend hold-up.

Police had previously said Sunday’s theft at the Carlton Intercontinental Hotel had netted €40 million ($53 million) worth of treasure — even at that level, one of biggest jewelry heists in recent years. 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.

Describing a canny — if quick and logistically simple — break-in, Vique said the suspect broke in through French doors at the hotel that open out onto Cannes’ famed Croisette, held up the participants of the show with a handgun, then fled on foot. The hold-up itself took place in the space of about a minute, and 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, adding there was not getaway vehicle. “He left on foot … it was very fast.”

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.