An ancient trading ship carrying wine that lay undiscovered at the bottom of the Mediterranean for more than 2,000 years has been damaged and looted since being discovered by archaeologists, French authorities said on Wednesday.

The ship, named Fort Royal 1, is thought to have sunk off the coast of Cannes on the French Riviera during the second century BC.

Divers tasked with the first official explorations of the wreck, which was discovered in 2017, found that some of the clay containers used to transport wine at the time had been removed by divers who had broken into the vessel.

“Well-conserved wrecks from this period are particularly rare,” said a joint statement from the department of marine archaeology in the French culture ministry and local police. “That’s why the opportunity to study the wooden body and the cargo is absolutely exceptional.”

“The losses of scientific and historical information are probably significant” as a result of the damage, it added, saying the thefts had been carried out recently and were ongoing.

The boat was discovered in 2017 by renowned French marine archaeologist couple Anne and Jean-Pierre Joncheray, who spent decades scouring the floor of the Mediterranean. Jean-Pierre Joncheray died in 2020 aged 79.

The area around the wreck “is now off-limits for moorings or sailing and an investigation has been opened by maritime police in Marseille,” the statement said.