The producer leading a television documentary team that says it has found 17th-century pirate William Kidd’s sunken ship fought back on Wednesday against a UNESCO report dismissing their claims. Sam Brown, who is making a film with marine archaeologist Barry Clifford, called UNESCO’s report a ‘disgrace’ and said the UN body was motivated by its opposition to privately-funded research. ‘UNESCO will attempt to discredit Barry Clifford by whatever means they can,’ Brown said in an email to AFP. ‘They have exhibited a frankly shocking lack of transparency and impartiality throughout. ‘They dived on the wreck site for less than four days in poor visibility and used very questionable methods.’ Clifford declared in May that he had located the wreck of Kidd’s legendary ‘Adventure Galley’ ship — and a 50-kilogramme (110-pound) silver ingot of plunder — off the coast of Madagascar.

Read More: UNESCO throws cold water over pirate William Kidd sunken treasure discovery