Media playback is unsupported on your device Media caption David Hughes, Park View Education Trust: ''The speed and the ferocity with which the school had been condemned was truly shocking''

A trust has denounced the decision to put three schools in special measures, as Ofsted prepares to publish reports on the alleged "Trojan Horse" plot.

The watchdog was called in after allegations of a hardline Muslim takeover of schools in Birmingham and has now inspected 21 schools.

It put six schools in special measures and said five had not done enough to protect children from extremist ideas.

But Park View Educational Trust said Ofsted had found no evidence of a plot.

The "Trojan Horse" row began with an anonymous letter, made public in March, alleging that a group of Muslims was attempting to usurp school governing bodies in Birmingham.

It has led to investigations by Birmingham City Council, the Department for Education (DfE), the Education Funding Agency and the schools watchdog Ofsted.

Ofsted is set to publish its 21 reports at 1400 BST on Monday.

Image copyright PA Image caption Park View School in Birmingham has been placed in special measures by Ofsted

The government confirmed that five schools that had previously rated as good or outstanding by Ofsted had now been rated inadequate in the reports.

In a statement David Hughes, Park View Educational Trust's vice chairman, confirmed that Park View, Golden Hillock and Nansen had all been placed in special measures by Ofsted - and said it would be challenging the reports.

"Ofsted inspectors came to our schools looking for extremism, looking for segregation, looking for proof that our children have religion forced upon them as part of an Islamic plot," he said.

"The Ofsted reports found absolutely no evidence of this because this is categorically not what is happening at our schools."

Media playback is unsupported on your device Media caption Mohammed Ashraf, governor of Golden Hillock School: ''Ofsted had a pre-set agenda to fail the school''

He said the school stood as a "beacon of hope against a tide of isolation, poverty, drugs, crime and yes, potential extremism".

"Park View is part of the solution, not part of the problem," he said.

However, a leaked draft report by the Education Funding Agency (EFA) - which has carried out a parallel investigation - said the Park View trust schools had "taken the Islamic focus too far".

It found girls and boys had been segregated in some classes.

In other developments:

The prime minister has chaired a meeting of the government's extremism taskforce - attended by Home Secretary Theresa May and Education Secretary Michael Gove

Mr Gove and Mrs May are both set to address the House of Commons

It comes after a row between the home secretary and the education secretary last week, which led to the resignation of Ms May's special adviser and an apology from Mr Gove

Downing Street has since said Ms May did not know about the decision to publish a letter attacking Mr Gove over the handling of the allegations

Shadow Home Secretary Yvette Cooper has been granted an urgent question in parliament over Ms May's actions

Birmingham Perry Barr Labour MP Khalid Mahmood meanwhile said it was vital that the inquiries dealt with everyone who had "manipulated what schools are there to do"

Brian Lightman, general secretary of the Association of School and College Lecturers (ASCL) union says "the constant cycle of leaks and accusations over the last few weeks will have been demoralising and damaging for students".

A separate inspection by Ofsted also found a Luton school does not "promote tolerance" and has books suggesting stoning and lashing as appropriate punishments.

The prime minister is set to ask Ofsted to bring in snap inspections for schools in England following the allegations.

Currently, schools can be inspected without notice usually only if they are rated inadequate for behaviour.

Image copyright PA Image caption The education trusts say inspections of schools, including Golden Hillock, were conducted in a "climate of suspicion"

Image copyright PA Image caption Michael Gove has 'sweeping powers of intervention'

'Robust response'

Last week, Mr Gove was involved in a bitter dispute with Home Secretary Theresa May over the government's response to the Birmingham allegations.

Mr Gove apologised to Mr Cameron and counter-terrorism chief Charles Farr after his allies spoke to the Times, accusing the Home Office of failing to "drain the swamp" of extremism.

In response, the Home Office released a letter which Home Secretary Theresa May had written to Mr Gove, accusing his department of failing to act when concerns about the Birmingham schools were brought to its attention in 2010.

Fiona Cunningham, the home secretary's special adviser, was found to have been the source of a negative briefing against Mr Gove and has now stood down.