A top Church of England school is to be placed into special measures after inspectors judged that it had failed to safeguard its pupils from extremism.

The Sir John Cass Foundation and Red Coat Church of England school in Tower Hamlets, east London has been criticised by the schools watchdog Ofsted for failing to monitor the activities of an Islamic society set up by sixth-formers at the school.

According to the report, leaked to The Independent newspaper, a Facebook page set up by the society contained links to extremist Islamists. The society also set up its own YouTube channel which the school failed to monitor.

Although comparisons have been made, the episode, in Tower Hamlets, east London, differs significantly from the so-called Trojan Horse affair in Birmingham where all the schools suspected of being subject to attempts of takeovers by extremists were not faith schools, but secular state schools.

The Tower Hamlets school comes under the auspices of the Diocese of London, which at the time of filing this story, had failed to respond to requests for comments. The Church of England head office directed all queries to the London diocese. Christian Today hopes to be able to update readers with a comment from the diocese at the earliest opportunity.

According to Ofsted, the failure to monitor the online activities of the sixth form Islamic group constituted a failure to safeguard the pupils and this was why the school had to be placed in special measures, in spite of twice previously being judged outstanding.

The school is also criticised in the report for allowing segregation between boys and girls in the playground, the Independent reports, adding that local education sources had accused Ofsted of over-reacting, saying the inspectors had taken "a sledgehammer to crack a nut". The playgrounds were segregated at the time of the two previous reports but this was not considered an issue at that time.

Segregation between the sexes is common in Britain's education system. Some schools have no girls at all, and other schools have no boys. Segregation is also permitted in other areas of British life. Some private members' clubs, for example, are permitted to exclude women entirely.

The Church of England this week ended an area of segregation for which it has been widely criticised, enacting legislation that allows women to be bishops. Mosques however can legally refuse to allow women to be imams, and women cannot be rabbis in Orthodox synagogues. The sexes are seated separately in many synagogues and all mosques, a legal form of segregation.

The report is to be published tomorrow, alongside reports on a further six schools which are also understood to raise safeguarding issues.

Future inspections by Ofsted are also expected to look closely at the increasing numbers of state schools with Islamic societies to ensure there are no comparable safeguarding issues.

The Tower Hamlets school's headteacher, Haydn Evans, who yesterday received an honorary degree from the University of East London for taking the school from being the lowest-performing in the country to "outstanding" status and who was awarded a CBE in the New Year's Honours List, is "shell-shocked" by the report's conclusions, according to The Independent.

Although the Tower Hamlets school is nominally Church of England, 80 per cent of its students are British Muslims whose families are of Bengali origin.

Robert McCulloch-Graham, corporate director of education for Tower Hamlets, said: "The inspection reports have not yet been published so we are unable to comment on the contents but what we can say is that when any issues in our maintained schools do occur, we have a strong track record of intervening swiftly and successfully to address them.

"We note that of the schools inspected, only one is a publicly-funded maintained school. As is common practice, we will work with the leadership of this school to address any issues identified by Ofsted. As a local education authority, we have no jurisdiction whatsoever over teaching and standards at independent faith schools. This is Ofsted's area of responsibility.

"We do, however, have responsibility for safeguarding all children in the borough and have always exercised our safeguarding duties to the full.

"We are working closely with Ofsted and the Department for Education (DfE) after their recent inspections and we will of course act on the findings of the reports. We will continue to work with Ofsted and the DfE to address any issues, potential or otherwise.

"The council and its partners have worked extremely hard to build the cohesive community that is Tower Hamlets and will do whatever is necessary to ensure that this continues."​