The police and the Independent Commission Against Corruption are no strangers to mutual tension. Even so, yesterday's action gave a stunning twist to their rivalry. For the first time, the police, who have been frequent targets of ICAC investigations, turned the tables, raiding the headquarters of the graft-busters over the alleged misconduct of three officers. The ICAC has long focused on fighting police corruption; the agency has a designated branch for the purpose. The ICAC's first important task after it was set up in 1974 was to bring police chief superintendent Peter Godber to justice after Godber had obtained more than HK$4 million in suspect assets. In 1977, thousands of police officers protested outside the ICAC headquarters over alleged persecution of the force. Some angry police officers even tried to break into ICAC offices in the incident. Confrontations between the two agencies flared into the open in 2002 when the ICAC arrested then police senior superintendent Sin Kam-wah, deputy head of the force's narcotics bureau, on suspicion of accepting sex in exchange for tip-offs about vice raids. The then commissioner of police Tsang Yam-pui, used a Legislative Council meeting to criticise angrily Sin's arrest. The police issued a statement saying the ICAC should have been more 'circumspect' about publicising the arrest. In the end, the then chief executive, Tung Chee-hwa, intervened by speaking to each agency's commissioner. After that, regular direct dialogue began between senior management of the two agencies to improve co-operation. Sin was convicted of accepting free sexual services from prostitutes in 2003. In 2005, the ICAC investigated Chief Superintendent Stephen Fung Kin-man, who led the police force's anti-triad operations, over a bribery case. Fung later jumped to his death in Kwai Chung. Last year the ICAC received 302 corruption reports concerning the police - 9 per cent of the total of 3,450 corruption reports for the year, excluding election-related cases. There were 268 such complaints in 2008.