A police document that listed climate change activists Extinction Rebellion alongside extremist groups was circulated to government departments, five police forces and 20 local councils - including Buckinghamshire County Council.

The Guardian reported that the guidance, produced by a counter-terror policing team covering south-east England, was widely circulated to bodies including the Home Office, the Department for Education and NHS England.

It was also sent to the Ministry of Defence, the Prison Service, probation service, schools watchdog Ofsted, several local authorities, five police forces and Counter Terrorism Policing headquarters (CTPHQ) in London, the newspaper said.

Members of the climate change campaign group, known as XR, have demanded an explanation.

A statement on the group's website said: "We need to find out who knew what and when. But more importantly, we need to know why.

"Why are they trying to silence a peaceful, non-violent movement of people who are trying to make sure the world's children have a future?"

XR member Rob Cooper, a former police chief superintendent, said: "The worrying aspect about these revelations is that nobody inside the police or at the Home Office thought to question the guidance that included Extinction Rebellion alongside extremist groups, when it was first produced, or when it was subsequently circulated.

"It is worrying that it seems to have slipped through the scrutiny net without any critical analysis."

The Guardian reported that XR had been listed alongside Islamist and extreme right-wing groups in the guidance that detailed warning signs of radicalisation.

A spokesman for CTPHQ said the document had not been opened by the contact who received it from the south-east team.

XR was included in the guidance due to "an error of judgment" and the document had been recalled.

He said: "CTPHQ was included in the wider email distribution list for this document. It was not sent for our review or approval, nor was it forwarded on by the individual that received it to others."

It was sent to five police forces - Thames Valley, Hampshire, Sussex, Surrey and Kent - and at least 19 councils: Milton Keynes, Slough, Bracknell Forest, Reading, Wokingham, West Berkshire, Royal Borough of Windsor and Maidenhead, Southampton, Portsmouth, Isle Of Wight, Brighton and Hove, Medway, Buckinghamshire, Oxfordshire, Surrey, Hampshire, East Sussex, West Sussex and Kent.

Last week security minister Brandon Lewis told MPs that XR was "in no way considered an extremist group".

Speaking in the House of Commons, he said: "We are clear that the right to peaceful protest is a cornerstone of our just society and an indispensable channel of political and social expression.

"The police have recalled the guidance and are reviewing it, and I want to reiterate that Extinction Rebellion is in no way considered an extremist group under the 2015 definition of extremism."