Mr. Sazonoff said it's normal for robbers to gravitate to a place such as Cannes, glimmering harbor and glamorous film festival of which attract the world's rich and famous.
"The brazen drama of it is their style. ... The possibility of the re-emergence of the Pink Panther gang is very troubling and taken seriously by law enforcement worldwide," Mr. Sazonoff said. "The theft of high-value diamonds is exactly what they do, so it's not a great leap to assume they are on the warpath again. They are a crime wave waiting to happen."