The head of England's qualifications watchdog has painted a picture of chaos in exam marking for key tests taken by all state school 11- and 14-year-olds. Ken Boston, chief executive of the Qualifications and Curriculum Authority, told MPs that markers had been given wrong information about the location and time of training, unmarked scripts had been incorrectly returned to schools, and markers had experienced delays in getting papers.

The marking of the exams - Key Stage Two and Key Stage Three - has been outsourced to ETS, the education company. Mr Boston was speaking before the children, schools and families select committee of the House of Commons, to which he had been summoned to explain this year's exam problems.