Seventy-eight pupils have had their results “withheld” while Edexcel investigates whether they benefited from the leaking of the exam board’s A level maths paper, Tes can reveal.

Pearson, the company which owns Edexcel, has now said that the entire paper was circulating on “closed social media networks” prior to the exam being sat. The company had initially reported that just two questions were leaked.

It also admitted that a separate A level exam paper which was criticised by some pupils for being too hard did start with two questions which were “more challenging than we typically expect initial questions to be”, although the board said the paper as a whole was “fair”.

Background: Edexcel investigating A-level maths exam leak

Criminal investigation: Two arrested by police over leak

Sharon Hague: ‘I regret the extra stress caused to teachers and pupils’

In June Tes revealed that blacked out images of two questions from Edexcel’s maths paper 3 were circulated on Twitter the night before the exam, accompanied by Tweets offering the whole paper for sale for £70.

The leak, believed to have taken place at a London school or college, is being investigated by the Metropolitan Police, who made two arrests in late June.

It was the third time Edexcel’s A level maths paper has been leaked in three years.

In a comment piece published on the Tes website this morning, Sharon Hague, head of Pearson’s UK schools business, provides an update on the actions which Edexcel has taken.

After the leak came to light, she says Edexcel “had to decide quickly whether or not to replace the paper - or reschedule the exam”.

“It was too late to replace papers and rescheduling would have caused significant additional stress and disruption for tens of thousands of students across the country.”

In the aftermath of the leak, Ms Hague had said that the two compromised questions could be removed from the overall assessment, but today she announces that this will not happen.

“Having now marked these questions we’ve made the decision not to remove them. This is because through our analysis we found that performance on these questions was as expected for the overall cohort.

“In the limited instances where we discovered anomalies - for example students scoring particularly well on these questions versus the rest of the paper - we have taken these students out of any further statistical analysis to determine the grade boundaries and have taken a closer look at their performance.”

She also confirms today that the entire paper was leaked online. “Subsequently it soon emerged that questions from the whole exam paper had been circulated by some students within closed social media networks,” she writes. “To be clear - our investigations team were not alerted to this or indeed able to confirm it until after the exam had been sat.”

Ms Hague said Edexcel was not able to immediately confirm this because “we get sent lots of images of question papers” but “the vast majority of these are hoaxes”.

“We were able to narrow the source of the breach down to one specific centre. We worked fast to interview the individuals involved, to understand the origin of the breach and to exclude their marks from results.

“Everyone we interviewed agreed to let us examine their phones with them as part of our own investigation and the police were also able to seize equipment from two people that they subsequently arrested. This police case is ongoing and we hope will end in a criminal prosecution.

“There are currently 78 students whose results we have withheld while we complete our malpractice procedures with them.”

Ms Hague says Edexcel will ensure “everyone is treated fairly” in the marking process because the board has tools allowing it to “look at student performance on individual questions on each paper to understand their relative difficulty”.

“We are then able to look at individual students’ performance on each question to see whether their performance was unexpected.”

In her article, Ms Hague also addresses claims from students that it’s A level maths paper 2 was “really hard” - the paper had sparked online petitions protesting against its difficulty.

“We want to reassure you that independent experts have analysed the papers and confirmed paper 2 was a fair and valid paper, testing across the ability range and the course curriculum,” she writes.

But she adds: “However, we do appreciate that the experience of sitting this paper, for some students, was not what they had expected in terms of the perceived level of difficulty. For example, we appreciate that the first two questions were more challenging than we typically expect initial questions to be.”

Ms Hague says that in the future Edexcel “will be looking to make some adjustments to our papers to improve students’ experience of sitting our exams”.

“It is regrettable a tiny number of people added to the stress of this year’s exams but every student should be confident that we mark and award to ensure fair results for all.”