lol, as if the British state was competent enough to infiltrate anything
Govts are competent at things the ruling class wants them to be competent at. Never forget that. Smashing any movement that can threaten their interests is high on that list so of course govts are pretty ok at infiltration.
The Metropolitan Police force had two groups they used to infiltrate activist groups, the Special Demonstration Squad (SDS) and the National Public Order Intelligence Unit (NPOIU). These two groups started their infiltration work in the 90s and continued until the 2010s, when this became public. I'm sure this work was moved to other groups after that happened.
This became public because one cop got carried away with being a big time activist and fucked up his opsec. His activists friends got suspicious and then the woman he had been in a long term relationship as part of his cover found his passport with his real name. The activists used that find his real identity and confronted him and then he confessed to them that he was really a cop. Indymedia UK wrote an article about this cop and the Guardian picked up the story from them. The Guardian wrote several more articles about cops infiltrating activist groups, (some of them are below) most of them focusing on the fact that the undercover cops (some of them married with kids) got into long term relationships with women as part of the their cover and in some cases, had children with these women, and then just bounced when the undercover operations were over. And I think the only reason the Guardian wrote about this because of the luridness of the cops tricking the women into relationships and abandoning their kids.
The cops are confirmed (which means the govt admitted to, who knows what they did that they didn't admit to) to have filtrated the following groups and movements:
Anarchist groups, Animal Liberation Front, Anti-Apartheid Movement, Anti-Fascist Action, Big Flame, Black Power movement, Brixton Hunt Saboteurs, Anglia Ruskin Churchill Society (Young Conservatives), Colin Roach Centre, Dambusters Mobilising Committee, Dissent!, Earth First!, Essex Hunt Saboteurs, Friends of Freedom Press Ltd, Globalise Resistance, Independent Labour Party, Independent Working Class Association, International Marxist Group, International Socialists, Irish National Liberation Solidarity Front, London Animal Action, London Animal Rights Coalition, London Boots Action Group, London Greenpeace, Militant, No Platform, Antifa, Operation Omega, Reclaim the Streets, Red Action, Republican Forum, Revolutionary Socialist Students Federation, Socialist Party (England and Wales), Socialist Workers Party, South London Animal Movement (SLAM), Tri-Continental, Troops Out Movement, Vietnam Solidarity Campaign, West London Hunt Saboteurs, Workers Revolutionary Party, Young Haganah, Young Liberals, Youth against Racism in Europe.
Mark Kennedy/Stone exposed as undercover cop (Indymedia)
Undercover police cleared 'to have sex with activists': Promiscuity 'regularly used as tactic', says former officer, contradicting claims from Acpo
Undercover police had children with activists
Undercover police officers' lies wrecked lives, say women they duped
Met facing mounting crisis as activist spying operation unravels
https://en.wikipedia.org/wiki/Undercover_Policing_Inquiry
https://en.wikipedia.org/wiki/UK_undercover_policing_relationships_scandal