The footage showed the guard, with other security personnel, chasing people in red boiler suits as they left while shouting: “You’re terrorists.”
Dennis said he detained two people, and the guard could be heard on video asking intruders who “wants it now?”
He told the jury: “I was irate. I was upset my colleagues had been hurt and the fact they thought this was acceptable behaviour.”
The prosecution allege the black team were there to overwhelm the guards, so the red team could enter the building and “smash up as much property as they could”.
The nine men and women on trial allegedly included members of the red team, one of the black team and others who helped at the perimeter and with travel and other arrangements.
The defendants are: Julija Brigadirova, 34, from Manchester; Nasser Akhtar, 39, of Crystal Palace; Elliot Wilson, 26 from Liverpool; Maximillian Dixon, 31, of Brockley, south-east London; Nirad Abrol, 27, of Birmingham; Seirol Davies, 31, from Plymouth; Xavi Davies, 23, of Binfield, Berkshire; Eoin O’Meara, 36, of Bristol; and Hannah Davidson, 53, of Edinburgh.
The trial continues.
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