Thousands of students face major grading change after A Level paper leak linked to Pakistan

The exam board confirmed material has been "circulated" in Pakistan, with a national cybercrime investigation being opened by officials in Islamabad.

Cambridge International also confirmed that AS and A Level maths papers had been leaked, as well as an AS computer science exam.

One pupil, Tobias Eatough, has now been forced to retake two exams because of the leaks and is struggling to recap the content alongside his other subjects.

The 18-year-old told Daily Mail: "From what I've seen, pretty much every single exam has been leaked. A couple of hours before, you get at least five people posting... And from there, it spreads."

Mr Eatough is sitting A Levels in maths, physics and biology and was hoping to get the three As needed to study medical biosciences at Imperial College London.

He added: "One of the papers that I felt went best has been cancelled, and they're now going to assign me a mark, which is just completely unfair. It feels like something that should be in my control, but it's completely out of my hands now. You do so much revision and you're not even sure if it will count."

Another pupil, who asked to remain anonymous, said: "I thought I had two weeks between my last exams and my next economics one. Now I have to revise all of that content at the same time - and these are hefty papers worth about 60 per cent of my grades."

"When I don't want to stress myself out on the morning of an exam, sometimes I just scroll on Instagram, and then I might see a paper.

The London-based teenager added: "It's just how it is now – you don't even have to look it up."

While Cambridge confirmed its AS computer science exam had been "shared prematurely in Pakistan" it did not necessarily mean it originated there.

Qualifications from Cambridge International are taken by pupils at almost 5,000 schools in 138 countries, including some independent schools in the UK.

The board has declared last Wednesday's physics AS and A Level papers void, with pupils receiving an "assessed mark."

In order to generate a pupil's new mark, the board creates a ranking of all the pupils in the world who take the same combination of modules.

Based on what they achieve in their other exams, they are awarded a corresponding mark for the one they did not sit.

A spokesman for Cambridge International said: "We have acted swiftly to put alternative measures in place for impacted students.

"It remains rare for the integrity of an exam to be compromised.

"The theft of these papers is the subject of an active investigation, and we are working closely with relevant law enforcement authorities and other partners."