A POLICEMAN was shot as he reached through the window of a hijacked taxi and wrapped his fingers around a gunman's throat, an inquest heard yesterday. The wounded officer pulled away and fired five shots, hitting the hijacker three times. Cheung Cho-yau, 23, and his handicapped Korean hostage, Kang Sang-bo, were killed in an Aberdeen gunbattle. Shortly after the taxi was stopped at a police roadblock, Senior Inspector Cheung Chiu-ping opened fire into the back seat, where Kang sat with his captor, the inquest heard earlier. Kang, 31, and Cheung Cho-yau were dying when police dragged them from the taxi. Constable Au Cheuk-yan testified yesterday that he had heard shooting before he reached the taxi. When he peered through the window of the vehicle, he saw the hostage slumped over, motionless, beside his captor. 'When I caught sight of this, the hijacker raised his pistol,' Constable Au said. He lunged through the open window and grabbed Cheung by the neck. As the policeman's fingers closed around his throat, Cheung pointed his gun over his shoulder and fired without looking, hitting the officer's shoulder. 'It happened very fast. I still had my arm around his neck,' Constable Au said. He pulled away and fired five shots, the inquest heard. 'After the fifth shot I felt safe,' he said. Constable Au said he fired without warning because the hijacker had shot him first. Only the gunman was endangered by his bullets, he said. 'It was a good target and it was a clear target. It was all done according to my training.' Coroner Warner Banks noted that none of Constable Au's bullets was to blame for Kang's death. The bullet that 'potentially killed him' was fired from the opposite side, where Senior Inspector Cheung had been seen earlier. The shootout marked the climax of a hostage drama that began in Central. At about 11.30 pm on October 13, Cheung Cho-yau put a gun to a patrolling officer's head and stole his revolver. Minutes later he grabbed a young woman and pushed her into a taxi. At that moment, Kang was entering from the opposite door. Cheung ordered the taxi driver to take him to Aberdeen, but the vehicle hit a roadblock near the Aberdeen waterfront. The gunman fired out of the window, the inquest heard earlier. As Cheung prepared to fire again, the Korean grabbed his wrist and began struggling for control of the gun. When taxi driver Ho Chun-ming, 40, turned around to help, female hostage Ku E-suen escaped, leaving the door open. Mr Ho said earlier a policeman then appeared in the doorway and opened fire into the back seat. The inquest continues.