Lauren Said-Moorhouse , CNN Lorenzo D'Agostino, CNN, Nicola Ruotolo, CNN Rome Written by

In a plot worthy of a Hollywood heist film, thieves mingled with other visitors to an exhibition in Venice on Wednesday before brazenly making off with gems of "indisputably elevated value," the canal city's police chief said.

The working theory being developed by investigating officers suggests that at least two people entered the Doge's Palace -- a popular tourist spot in Venice where a selection of Indian jewelry from the Qatari royal collection was on display to the public.

One suspect acted as lookout while the other grabbed the jewels from a display case, police believe.

Venice Police Chief Vito Danilo Gagliardi said that the stolen items were a pair of earrings and a brooch made of diamonds, gold and platinum. The pieces -- owned by Sheikh Hamad bin Abdullah Al Thani -- were snatched in the bold daytime robbery on the last day of the exhibit.

A poster indicating the precious display hangs from Venice's Doge's Palace. Credit: Andrea Merola/AP

A preliminary investigation revealed that the pair were able to delay the alarm system for one minute so it wasn't triggered until the thieves were making their escape, Gagliardi said. He described the culprits as "skilled."

"They were certainly well prepared and hit in a targeted way," Gagliardi said.

Over 270 pieces of Indian Mughal jewelry dated from the 16th to the 20th century were being shown to the public. Credit: Andrea Merola/AP

The police chief suggested the jewels would be difficult to sell on because of their international recognition and might, therefore, be disassembled and sold separately.

Gagliardi earlier told Reuters that the jewels had a customs value of 30,000 euros (around $31,000), but indicated that the actual worth is more likely "a few million euros."

A Venice police spokesman told CNN that the stolen pieces were "of great value" but would not provide an exact estimate of their worth.

















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The spokesman added that authorities arrived at the scene at 10:17 a.m. (3:17 a.m. ET) on Wednesday after being alerted by the head of security, who told them that "some jewels had gone missing."

In a press release, the Doge's Palace confirmed the theft of "two objects" from the Al Thani Collection. The objects were described as "recently made and of marginal value compared to other jewels of greater historical value."

"Thanks to the timely intervention of the security apparatus operating inside the exhibition halls, and whose definition was shared from the outset with the Venice Police Headquarters, the Civic Museums Foundation was able to provide all the law enforcement agencies the elements necessary for a rapid solution of the ongoing investigation," the statement continued.

The door to the exhibition room is closed following a jewel theft on Wednesday morning. Credit: Andrea Merola/AP

The exhibition displayed over 270 pieces of Indian Mughal jewelry from the 16th to the 20th century, according to the Doge's Palace website.

The exhibition closed yesterday on schedule.