A spy who infiltrated a direct action anti-aviation group has been exposed after making a series of elementary errors that aroused the suspicions of genuine activists.

Toby Kendall joined Plane Stupid, the group that occupied the roof of the Houses of Parliament last month, after graduating from Oxford last year. He told the activists that his name was “Ken Tobias” and said that he was deeply concerned by the impact of the aviation industry on climate change and that he wanted to help to organise protests.

But his habit of wearing a Palestinian scarf with his Armani jeans and designer shirt made some members question his identity. He was also the only member to turn up early to every meeting but had no friends in the activist community. He took part in protests, dressing as a penguin in one stunt, but always tried to remain in the background.

Plane Stupid began a mole hunt and, after feeding him false information that found its way within two days to the aviation industry, discovered his real name and employer.

Mr Kendall, 24, works for C2i International, a counter-intelligence company run by former special forces officers. It claims that its agents are “hand-picked from Special Operations at New Scotland Yard”. Its website puts “aerospace” at the top of a list of industries for which it works.

BAA, which owns Heathrow, has repeatedly been targeted by Plane Stupid. When asked by The Times whether it had any connection with C2i or Toby Kendall, BAA said: “BAA can categorically state that we do not have a relationship with C2i or the individual in question.”

After being asked more detailed questions, BAA said it “had no contact with the named individuals but was subject to an unsolicited pitch by C2i. We rejected their invitation to enter into an arrangement with them.”

Justin King, C2i’s managing director, claimed to have been unaware of Mr Kendall’s infiltration of Plane Stupid. He said Mr Kendall was employed to carry out counter-surveillance such as “debugging company offices”.

He added: “The security industry is full of people on the circuit who masquerade as this and that. When they are not working for us how can we stop them from working for other people?” Asked how he felt about one of his team infiltrating a protest group, he said: “I’m not particularly happy about it. We will have to look into it.”

Mr Kendall failed to return calls yesterday and appears to have gone to ground after being confronted by members of Plane Stupid.

A spokesman for the group said: “This special agent was more Austin Powers than James Bond, though the question still remains, who paid for the spy?”

Times Recommends

• Lies and cover-up at MG Rover exposed by report
• High oil prices push manufacturing costs up
• Primark founder steps down as chief executive