Police were searching across France Tuesday for 17 stolen endangered monkeys that could fetch tens of thousands of dollars on the black market.

The seven golden lion tamarins and 10 silver marmosets, all owned by Brazil, were taken Saturday from the Beauval zoo south of Paris, the zoo’s director told Reuters.

"It's an outrageous theft. These are extremely fragile animals that need specific care," Rodolphe Debord said.

Zoo officials described a sophisticated break-in where the thieves cut through a glass window to steal the monkeys. Police are now reviewing surveillance footage.

The tamarins – which have specific dietary requirements – can fetch between $5,600 to $11,240 each on the black market, Reuters reports.

“There are two possibilities. Either a collector or the black market for new types of pets," Debord said.

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