Extinction Rebellion has defended its activists after being listed as an "extremist ideology" in a document produced by counter-terrorism police.
The climate activist group was placed in a document entitled "safeguarding young people and adults from ideological extremism", the Guardian reports.
The document, aimed at police officers, government organisations and teachers who by law have to report concerns about radicalisation, contained a whole page on Extinction Rebellion, also known as XR, and said they were a threat due to having "an anti-establishment philosophy".
It added that "while non-violent against persons, the campaign encourages other law-breaking activities".
It also highlighted the group's logo and some of its slogans as things to watch out for.
Those behind the document have since said they accepted that the protest group was not extremist. The document is set to be pulled from circulation.
In a statement, XR said: "How dare they. Children up and down the country are desperately fighting for a future. Teachers, grandparents, nurses have been trying their best with loving nonviolence to get politicians and big business to do something about the dire state of our planet.
"And this is how the Establishment responds.
"In a world of misinformation, where lies travel faster than the truth, we can’t help but wonder was this a deliberate attempt to silence a legitimate cause."
They also said that a "record number" of people in the UK expressed a concern over climate change in 2019.
DCS Kath Barnes, the head of Counter Terrorism Policing South East which produced the document, told the Guardian the group's inclusion was an error.
She said: “I would like to make it quite clear that we do not classify Extinction Rebellion as an extremist organisation.
"The inclusion of Extinction Rebellion in this document was an error of judgment and we will now be reviewing all of the contents as a result."
The group rose to prominence last year as it held massive protests in London, throughout the UK and across the globe last year.
It brought London to a standstill and thousands of its members were arrested as they blocked roads.