The CII has apologised after losing 35 test papers of candidates sitting one of its exams, meaning they may have to re-sit the module.
The papers were lost after being signed across to a courier following the exam sitting in London last month for the CF5 module, part of the Certificate in Financial Planning.
David Ross, director of communications at the CII, described the loss as "unprecedented" and said the organisation was taking responsibility for it.
"We've told everybody that's affected and clearly we've apologised. Clearly the courier's still looking and we're looking for the papers," he said.
"Today, our people were at the courier's operations in London helping to look for them and ensuring that we try our best to keep on top of this."
He said the CII was "angry and frustrated" with the courier service and added the candidates have all been offered a free re-sit, with no extra charge, as well as a revision day.
"We can't just pass people for exams so the only option open to us is to offer a re-sit, which we've done," Ross explained.
"It's disappointing and we're very sorry.
"Other candidates should be reassured we take our responsibilities very seriously and clearly we will be working with the courier to review their processes to make sure this doesn't happen again."
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