Two examiners have been suspended following allegations that teachers were given unfair advice on how to improve pupils' GCSE and A-level results.
It comes as an urgent inquiry ordered by ministers began into claims that teachers attending seminars run by exam boards were given detailed advice on forthcoming questions and how students could score higher marks.
A spokesman for the Welsh exam board WJEC said: "Two history examiners have been suspended."
WJEC also confirmed that it has begun its own inquiry into allegations made in the Daily Telegraph, and it is hoped that this will report back by the end of Friday.
England's exams regulator Ofqual has warned that exam boards could be forced to rewrite next year's GCSE and A-level papers if it is found that teachers were given unfair advice on how to boost results.
Education Secretary Michael Gove has ordered Ofqual to look into the Telegraph's claims, and report back by Christmas.
According to an investigation by the newspaper, teachers paid up to £230 a day for seminars hosted by chief examiners. During some of these seminars they were allegedly given advice on the wording students should use to increase their marks and which questions they were likely to face.
Ofqual chief executive Glenys Stacey said that the regulator could order exam boards to rewrite papers if it is shown that improper advice was given to teachers.
She told BBC Radio 4 that it was "certainly not acceptable" for examining bodies to tell teachers about the "cycle" of question-setting, so that they have a good idea what questions their pupils will face.
It is understood that the awarding bodies involved have pledged to investigate whether individual examiners broke the rules.