Boris Johnson has blamed a "mutant algorithm" for the A-level results debacle before sacking the most senior official at the Department for Education.

Labour's Shadow Education Secretary Kate Green accused the Prime Minister of "shamelessly trying to avoid taking responsibility for the exams fiasco that his government created".

Jonathan Slater is the second top official to leave their job in the wake of the scandal, after it was announced on Tuesday that Ofqual's chief regulator Sally Collier would depart her position.

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