A policeman has denied disguising himself as an anti-government protester in an attempt to incite others to storm the force’s headquarters at the trial of a demonstrator accused of rioting and assault during the social unrest last summer. Constable Cheung Kam-fuk recalled the incident as he testified in the District Court against construction worker Shum Hiu-lun, 26, who has denied both charges stemming from the siege of the Wan Chai police headquarters on the night of June 26 last year. The officer has come under the media spotlight over speculation he posed as a protester during the incident following a peaceful demonstration in Central against the now-withdrawn extradition bill. Video footage played in court showed the officer in a grey T-shirt and brown shorts running from the crowd gathered outside the headquarters, then fleeing up an escalator to take temporary shelter outside the main entrance on the building’s upper ground floor, which was closed off at the time. He was then seen picking up a traffic cone and a squeegee, while protesters shone laser lights at him. He eventually entered the police building with the help of colleagues. At Tuesday’s hearing, Cheung denied he pretended to be a protester to encourage the crowd to break into the headquarters, saying he went to Wan Chai after a supervisor called him to help protect the building. But upon arriving at 11.30pm, all the entrances were blocked by the crowd, he told the court. Several protesters approached him and identified him as an officer even though he never showed his police card and began to harass him, Cheung said. Demonstrators started to chase him as he circled around the headquarters looking for a way inside. Some swore at him, grabbed his arms and kicked his legs, he said. A masked protester – identified by prosecutors as Shum – punched his face, leaving him bleeding at the mouth, Cheung told the court. He ran up the escalator and picked up nearby objects for self-defence in case he was pursued. “I feared the protesters might run up [the escalator], and at that moment, I found a traffic cone and a window cleaner, so I casually picked them up to defend myself,” he said. “At that time, I had my back to the wall.” Defence counsel Anthony Lai suggested the masked person who hit Cheung might have intended to stop him from fleeing, after witnessing the officer pushing a woman protester to the ground during the chase. Cheung denied assaulting her but admitted he pushed her aside because he was trying to get away from the crowd. Shum has admitted to a lesser count of taking part in an unlawful assembly during the disturbance, but the prosecution rejected the plea. He also pleaded guilty to failing to surrender to custody after skipping a pretrial hearing while on bail. The trial before District Judge Anthony Kwok Kai-on is expected to last seven to 10 days.