Ofsted has "questions to answer" over its role in the Trojan Horse scandal that has engulfed a raft of schools in Birmingham, Labour's education spokesman has said.
Tristram Hunt said the schools watchdog was implicated in the crisis, which has seen suggestions of pupils being exposed to extremism.
Speaking at a Policy Exchange conference in London this morning, Mr Hunt said there had been "systemic failings" at the Department for Education in the scandal, but he also highlighted Ofsted's role.
"Clearly, given that some of these schools received positive Ofsted ratings in the not too distant past, there are also questions for Her Majesty’s Inspectorate," he said.
Talking to TES after his speech, Mr Hunt added that there needed to be an overhaul of the inspection criteria.
"Parents will be confused that schools can go from "outstanding" to "requires improvement" in such a rapid period of time, and that raises questions of around the inspection criteria."
Labour, he said, would oversee an overhaul of the inspection regime that would ensure a fifth criteria was put in place for schools to be judged outstanding, which would call for schools to deliver a "broad and balanced" curriculum.
His comments come as one school, Park View Academy, which is at the centre of the Trojan Horse scandal, has seen its rating downgraded to "inadequate" for not doing enough to protect its students from extremism.
Mr Hunt said his opposite number, education secretary Michael Gove, had been guilty of "gross negligence" when it came to the whole affair and demanded the cabinet member answer questions in the House of Commons on Monday.
TES understands the Ofsted report into the Birmingham schools could be brought forward to Monday due to the seriousness of the allegations.
The scandal led to a very public spat between Mr Gove and home secretary Theresa May after Mrs May's office published a letter addressed to the education secretary questioning his actions over Trojan Horse.
In his speech today, Mr Hunt quoted a Home Office source as saying: "Lord knows what more they have overlooked on the subject of the protection of kids in state schools. It scares me."