Thousands of junior doctors have been left in the lurch over their first medical jobs after marking errors in their final exams.

On Monday the majority of the 7,200 trainee medics were told to which institute they had been assigned, based on their exam results.

But on Tuesday examining body the UK Foundation Programme Office (UKFPO) withdrew the offers after admitting there were flaws in the marking system.

The BMA said the situation was “unacceptable”.

The programme office announced that it had discovered “a potential error in the scanning process of the Situational Judgment Test”, and promised to manually re-mark the tests within a week.

“The UKFPO and Medical Schools Council do not underestimate the anxiety that this may cause, and are working collaboratively to resolve this issue as quickly as possible,” the examining body said.

Results of the test determine where the students will work for the duration of their Foundation Programme - a two-year training course which forms the bridge between medical school and training for a specialism.

BMA medical students committee co-chair Alice Rutter said: “Students who initially will have been delighted to receive their foundation school allocation may now be concerned that their job could be at risk.

“This is completely unacceptable. We view this problem very seriously indeed and will be taking action to ensure students who are affected are kept updated and supported.”

Dr Ben Molyneux, chair of the BMA’s Junior Doctors’ Committee said: “It is regrettable that these errors have occurred and the UKFPO must find a fair and appropriate solution to ensure that these students are able to take up their posts in the hospitals.

“Junior doctors must have confidence that the application process is fit for purpose.”

Ms Rutter added: “This is a completely unacceptable situation, especially as it appears that the UKFPO had early indications of problems with the application system yet decided not to halt the process of allocating students to their first job.

“It is important that the UKFPO gets a grip on this situation quickly.

“Medical students must be told exactly when they will hear about any changes to their application and any re-marking should be done as soon as possible. Given the levels of anxiety students will now be feeling there can be no room for uncertainty about when they should expect advice about their revised offer.

“Some students would have already been making important decisions built around where their first job would have been, including signing rental leases for flat-shares.”

A Department of Health spokeswoman said: “The UKFPO is working urgently to resolve this so there is minimum disruption to doctors and hospitals affected, and that everyone concerned can be notified as quickly as possible about junior doctor job placements for August.

“This error should not have happened and we are concerned about the anxiety this could cause some students.

“We remain clear that all eligible graduates of a UK medical school will receive a training place for August 2013.”