The transfer of Xavier Tang Kam-moon from one of the most senior positions in the Hong Kong Police Force has been as rapid as his rise through the senior ranks. The 49-year-old joined the force in 1979 as an inspector and was twice honoured by the government for his crime-fighting efforts. He has spent most of his 26 years on the force doing criminal investigation and has worked for the Narcotics Bureau and the Organised Crime and Triad Bureau. After being appointed a chief superintendent in 1998, he became the head of the Criminal Intelligence Bureau, and later the deputy regional commander of New Territories South Region. He jointly led a special taskforce to track every move of notorious gangster 'Big Spender' Cheung Tze-keung, who was later executed in controversial circumstances on the mainland. In the 1998 Bauhinia list, he received the Hong Kong Police Medal for Meritorious Service for his 'exemplary and devoted service in the Hong Kong Police Force'. He was promoted to the rank of assistant commissioner of police in December 2003 and was appointed regional commander of Hong Kong Island Region in May last year. His promotion to assistant commissioner was part of one of the biggest shake-ups of the force's hierarchy following the retirement of former commissioner Tsang Yam-pui, who was succeeded by Dick Lee Ming-kwai. Mr Tsang, younger brother of Chief Executive Donald Tsang Yam-kuen, was a strong supporter of Mr Tang. But police sources say some current senior officers were less so. Disgruntled officers also privately voiced concerns about his handling of the region, with some wanting to transfer to Hong Kong Island. 'The WTO was an acid test for Tang. It was felt by some that he hadn't grasped the bigger picture of such a big operation properly,' one said. Another said Mr Tang was annoyed he was effectively 'left out of the loop' for the security operation, with Mr Lee appointing field commanders to handle the job. 'He tried to micro-manage the situation, but some officers felt he could have handled it better,' the source said. Mr Tang is understood to have been angered by the transfer. One source claimed he wasn't in the mood for Christmas celebrations after the WTO finished. 'Normally, on December 23 they [many senior officers] go for a Christmas party and it's taken as a given that the officers finish for the day and don't come back to work,' another police source said. 'This year, especially, we were expecting the same thing to happen as a pat on the back for the work done during the WTO. But, he called everyone back to the office at 2.30pm.' Mr Tang will move to the position of assistant commissioner of police (personnel) on January 16. His replacement is expected to be Paul Hung Hak-wai, who is now assistant commissioner of police (support).