Undercover police spies unmasked - in pictures

Bob Lambert in the 1980s, when he infiltrated environmental and animal rights activists using the alias Bob Robinson Photograph: Guardian

Lambert holding the child he fathered with an activist while he was undercover. The spy, who infiltrated environmental and animal rights campaigners in the 1980s, had sexual relationships with four women Photograph: Guardian

Lambert co-wrote the famous 'McLibel' leaflet that defamed McDonald's and cost the fastfood chain millions of pounds in legal fees. Here, Lambert (right) hands out copies of the leaflet outside a branch of the chain in October 1986 Photograph: Guardian

Mike Chitty infiltrated animal rights campaigners in the 1980s using the alias Mike Blake Photograph: Guardian

Chitty is pictured at a camp in Devon protesting against government plans to kill badgers in 1986. He later went skinny-dipping in a river with campaigners Photograph: Guardian

John Dines posed as an environmental activist between 1987 and 1992, and had a two-year relationship with the campaigner Helen Steel. She was later one of two defendants in the 'McLibel' case, in which McDonald's sued activists over a leaflet that criticised the burger chain
Photograph: Courtesy Helen Steel

Dines pictured while he was undercover, pretending to be a campaigner called John Barker in the early 1990s. He was one of many spies who stole the identities of dead children to make his alter ego more credible Photograph: Guardian

Mark Jenner pretended to be a leftwing activist in the 1990s, sharing a flat with his girlfriend for four years. Throughout their relationship, he concealed his real identity and occupation from her before disappearing without trace Photograph: Guardian

Jim Boyling posed as a campaigner in the Reclaim the Streets environmental campaign in the 1990s. Claiming to be a cleaner called Jim Sutton, he had previously infiltrated activists campaigning against fox hunting Photograph: Guardian

Boyling is being investigated over claims that he gave false evidence under oath in a court case. While undercover, he was prosecuted alongside anti-car campaigners but concealed the fact that he was a police spy from the court Photograph: Guardian

Lynn Watson, the only known woman undercover police officer, dressed as a clown at an anti-war protest in Leeds in 2004 Photograph: Guardian

Watson spent five years in the 2000s pretending to be a committed leftwing campaigner Photograph: Guardian

Marco Jacobs spent four years posing as an anarchist truck driver in Cardiff Photograph: Guardian

Jacobs spent four years infiltrating anarchists in Cardiff, and is said in legal papers to have had sexual relationships with two activists Photograph: Guardian

Mark Kennedy, who spied on political campaigners for seven years, gives a thumbs-up at his 40th birthday party at a farm in Herefordshire in September 2009. He disappeared shortly afterwards, claiming to be suffering from a breakdown Photograph: Guardian

Kennedy poses for a media interview in 2011, a few weeks after the Guardian first revealed details of his seven-year deployment Photograph: Philipp Ebeling for the Guardian