Police have refuted speculation a fourth person was involved in Friday's shootout in Tsim Sha Tsui. Assistant Commissioner of Police Lee Ka-chiu confirmed today investigations indicate only three people were involved, meaning there were no suspects at large.

A Police Constable and the male suspect were killed, and another constable wounded, in the shootout, which Mr Lee described as an exceptional and isolated case. A death inquest is pending.

Mr Lee said the suspect, an off-duty constable, was acting alone and his action was premeditated, aiming to steal the two patrolling officers' guns and ammunition. It was confirmed he had used the Police-issue revolver stolen from constable Leung Shing-yan, shot dead in Tsuen Wan in 2001. It was also used to kill a security guard in a bank robbery on Castle Peak Road later that year.

The suspect knew neither Constable Leung nor the two patrolling officers, Mr Lee said, adding investigations are now focused on the suspect's psychological condition and his motive, refuting reports money was involved.

Police interviewed about 3,000 people in the Leung Shing-yan case, among them 2,000 officers, but the suspect was not included.