An investigation has been launched after an A-Level maths paper was leaked the night before the exam.
An anonymous person was selling the answers to students for £300 last night while sharing the first question in a bid to lure in buyers.
The examination, was sat by 50,000 pupils across the UK today, was created by EdExcel one of the biggest exam boards in the country.
The firm, owned by Pearson, has said tonight it is investigation allegations of a ‘breach of security’ and has passed a file to the police.
The leak comes a year after the same C4 Maths paper – published by EdExcel – was leaked to students.
Leaked: The EdExcel maths paper for A-Level students was distributed on the internet the night before the exam
A man was arrested by the Met Police but without charge. Pearson said the investigation is ongoing.
Anyone found guilty of leaking the papers could be charged with theft, if the exam paper has been improperly obtained.
Speaking today, a spokesman for Pearson on behalf of EdExcel told MailOnline a man had been arrested last year but said they did not work for EdExcel and had never been employed by them.
Questions have been raised about how the same paper could have come to be circulated again online a year later.
Furious students spoke of their annoyance at sitting a test that had been touted online for money.
Disappointed: A Level student Andrew Condon was one of thousands sitting the exam today
Andrew Condon, 18, told MailOnline he thought the person responsible for the leak should be held to account.
The student at Tiffin School, a leading all boys grammar school in Kingston-upon-Thames, said he feared if too many people had access to the answers, markers may be harsher in their judgement.
The teenager, who has a conditional offer at Durham University, said: ‘It was all over Twitter last night, the night before our exam today.
‘I was really annoyed because obviously I and a lot of other students had been studying really hard and didn’t have this advantage.
Andrew has applied to study Politics, Philosophy and Econmics but fears he might miss out if he doesn’t make the A* grade required in the maths paper he sat today.
He said: ‘It’s annoying and unfair to know some people may have sat the exam knowing the answers. And examiners won’t be able to tell.’
While student Rhitik Raja wrote on Twitter that he was ‘absolutely appalled’, writing that he worried that ‘hundreds of people are not going to get the grades they deserve’ due to the error.
Another wrote: ‘@Edexcel. The C4 maths paper 2018 was leaked. This is not fair on the students who actually revised for this exam without knowing the paper. What are you going to do about it!?’
Viral: Students from across the country were sharing
He added: ‘I’ve been revising since Easter, it’s really annoying that after all this hard work someone is asking for £300 for the whole paper.
‘I found the exam all right but some of my friends who struggle with maths said they found it much more difficult than they expected.
‘Whoever did it, shouldn’t be leaking papers, it’s not their job.’
In a statement to MailOnline, a spokesman for EdExcel said: ‘Pearson has been made aware of allegations of a limited breach of security relating to the GCE Mathematics C4 examination.
As is usual practice in these circumstances, we have opened an investigation into whether there has been any exam malpractice. We are also contacting the police on this issue.
‘We’d like to reassure all students that the planned exams next week will continue as scheduled and that we have established processes in place to ensure no students will be advantaged or disadvantaged in any way.
‘If anybody has information about exam malpractice they would like to share with us in confidence they can contact us at pqsmalpractice@pearson.com.’
Exam and assessment regulator Ofqual said it was working with Pearson, owner of exam board Edexcel, to ‘establish the facts’ after the C4 maths exam apparently surfaced on the internet.