It is a matter of profound regret to me that examinations for two of this year’s A-levels, economics and maths, have been overshadowed by concerns about whether or not content from the papers was made available before the exams were sat.

This situation has caused anxiety for schools, teachers, students and their parents. Many will have questions about whether we acted in students’ best interests. Because we‘d been working with the police in a confidential investigation, we were not able to comment publicly on the work we were doing.

We now have permission from the police to mention their investigation, so – at the earliest opportunity – I want to explain the approach we have taken.

In the case of last week’s economics A-level, we were alerted to a possible breach in one school that resulted in some high-level content posted on social media 20 minutes before the start of the exam. This contained no precise details about specific questions and we do not believe any student has been advantaged, although we will monitor trends closely. We have moved quickly to identify the individuals concerned and will be following established disciplinary procedures.

The circumstances surrounding maths A-level were more complex and concerning, with someone apparently offering papers for sale online, which is not only grossly unfair to all other students – it is also a criminal matter.

As a result of intelligence shared with us by students, the sale of exam papers was confirmed on Friday 23rd June – too late to replace papers to be sat that day and the following Monday. We notified the exams regulator Ofqual, and took the evidence we had gathered to the police who immediately began their investigations.

The police rapidly made arrests, but their detailed investigation takes time, and we had to make a decision about how to approach the exams that students still had to sit. In any situation like this we have well-established contingency plans that adhere to one overriding principle – fairness for all students. We have to ensure that the exams are secure, and that we will be able to mark papers to ensure fair results.

If we had had any reason to believe that there had been a widespread breach of the maths papers, we would have postponed this week’s sittings without hesitation. We did not have reason to believe the breach was widespread, and considered a move in the exam date would potentially disadvantage a large number of students.

The police enquiries suggested that the problem was localised, so we decided that the best approach was to issue replacement questions for the papers to be sat in the small number schools and colleges that were in the area where specific concerns had been raised with us. This is something that we prepare for, so on Monday morning, our staff visited those centres to help teachers issue the replacement questions.

It is regrettable a tiny number of people added to the stress of this year’s exams

In any situation where there is even a suggestion that the content of exam papers has been breached, we undertake additional statistical analysis once the marking is completed to establish whether there are patterns in the results that are unusual for a particular centre or student, to be found. We will take this approach to the marking and awarding of this year’s maths A-level. No student will be asked to re-take a paper and every student should be confident that we will mark and award maths A-level and ensure fair marking and fair results. That guides everything we do, working with the other exam boards and the regulator to be certain that every student gets the grades that he or she deserves.

It is regrettable that a tiny number of people have added to the stress of this year’s exams. We’ve acted swiftly and have taken the right steps to ensure the fairness of the exams.

Exams are an integral part of our education system, and a professional and fair exam system is underpinned by a strong partnership between exam boards and the schools and teachers we work with every day. We are grateful to all teachers and students for their understanding and for working with us over the exam season.

Rod Bristow is President of Pearson UK