Two men have been arrested as part of an investigation into an A-level maths exam security breach, which led the Edexcel board to withdraw and replace a second A-level paper over fears it had also been leaked.

The Metropolitan police said two men aged 29 and 32 were arrested on Monday on suspicion of theft. The men have been released under investigation while inquiries continue.

The potential leak was uncovered during an investigation at an unnamed school earlier suspected of being the source of an A-level maths paper that was being offered for sale via social media this month.

Pearson, Edexcel’s parent company, replaced a further maths paper with a new version as a precaution two days before 7,000 pupils took the exam last Thursday.

News: Police confirm arrests have been made in the breach of ​our​ A level maths paper​ https://t.co/an9PULiaLW — Pearson Edexcel (@PearsonEdexcel) June 25, 2019

Sharon Hague, Pearson’s senior vice-president for schools, said: “The actions we have taken to strengthen our security processes have enabled us, in conjunction with the police, to quickly identify those who we believe were involved in the breach and to take swift and immediate action.”

She added: “We are systematically working through all leads and, as we continue to investigate the suspects, this will enable us to further home in on anyone that has gained an advantage, and take action accordingly. Our key priority is ensuring no students are disadvantaged in any way.”

Last week Pearson said its investigation had revealed that a sealed packet containing the further maths paper had been “opened by an individual” at the school, although it said it had no evidence that any questions had been leaked. Schools are required to securely store papers until immediately before each exam is taken.

The breach is the latest example of poor security involving lost or stolen papers that have plagued examination boards in recent years, with leaked papers rapidly copied and distributed online.

On Sunday the Guardian revealed that police had been called in to investigate another exam leak after some students had advance sight of part of a AQA GCSE religious studies paper last month. AQA confirmed police had been contacted and an investigation was under way.

In 2017, Pearson was forced to make changes to statistics and further pure maths A-level papers after reports that some students had seen questions in advance. And in 2017 and 2018, police investigated suspected leaks of Edexcel’s A-level maths papers and 29 candidates had their results annulled. A criminal investigation into the 2017 case continues, with details forwarded to prosecutors last April.

Pearson stressed on Tuesday that the strict security requirements for the exam system were based on trust. It said: “We are sorry that the actions of a small number of individuals have resulted in such a breach.”

Ofqual, the exam regulator for England, plans to investigate what can be done to protect the integrity of exams after this summer’s results season.