Mark Kennedy spent seven years pretending to be a climate activist. People he deceived are still rebuilding their lives.
The undercover officer made the comments at the inquiry into police spying on protest movements in the 70s and 80s.
Politicians and campaigners say that the remarks confirm the long-held suspicion that police spying was sanctioned by the top levels of government.
'We’re Going Up Against the State Here': The UK's Victims of Deep Undercover Policing Tell of Their Trauma
The UK government has announced the details of a new inquiry into undercover policing. VICE News spoke to some of the activists still haunted by the fact that so many of their friends turned out to be spies.