September 20, 1998, is remembered as 'Black September' by Anwar Ibrahim's supporters and democracy activists.
That night a crack police team raided Mr Anwar's house in the upscale Damansara suburb, roughed up supporters crowding the place, and 'captured' the former deputy prime minister.
Mr Anwar had just returned from a week of nationwide rallies during which he had attacked corruption and cronyism under prime minister Mahathir Mohamad, who had sacked his deputy on September 2.
Mr Anwar was taken to the police headquarters, handcuffed and blindfolded and thrown into a cell. At about midnight, the inspector-general of police, Rahim Noor, entered the cell, made derogatory remarks and beat him up, causing severe face, neck and eye injuries.
Sympathetic police officers leaked news of the assault to the world, but Dr Mahathir and Mr Rahim assured everyone that Mr Anwar was in custody and in fine health.
Sceptical American, Australian and European governments pressed Dr Mahathir to produce Mr Anwar, and five days after the assault Mr Anwar was led into a court with a huge black eye, sparking a storm of protest.
Police pretended at first not to know who had assaulted Mr Anwar, but in January 1999 the government admitted police did it, although it did not identify a culprit.
The following month, Mr Rahim, who had 30 years of otherwise exemplary service behind him, confessed before a public inquiry that he had beaten Mr Anwar - and promptly resigned.
Mr Anwar's black eye became a political symbol, with images helping the opposition make significant gains in the 1999 election.
Lee Kuan Yew, modern Singapore's founding father, described the black eye incident an 'unmitigated disaster' for the country and Dr Mahathir in a visit in 2002.