Jan 31: Police say they have arrested one Chung Yik Tin, 29, in connection with the case. Feb 1: The man is charged with publishing an "obscene" photo, and is refused bail.
Feb 2: Police arrest four men and two women in connection with the case.
Feb 3: Police arrest another man.
Feb 4: Police say one of the men they arrested, a 23-year-old technician, is the source of the leaked photos. He is believed to have copied the photos from Chen's laptop when it was sent for repair in 2006. Chen, who is believed to be away in the United States, apologises for the scandal in a video.
Feb 5: At least four new photos are sent out online.
Feb 6: More than 200 new photos surface, showing three new faces: model Rachel Ngan, former singer Candice Chan and former beauty contestant Mandy Chen.
Feb 9: Edison Chen's girlfriend, student Vincy Yeung, shows up in three new photos, which are sent out with more than 200 new ones.
Feb 10: Hundreds of Netizens hold a protest march, saying the police handling of the case is a violation of rights and that the celebrities are receiving privileged treatment.
Feb 11: Gillian Chung apologises, saying she was "naive and very silly". Police say they have arrested another man.
Feb 14: Two new photos are posted. One shows Edison Chen and Bobo Chan and the other, Ngan.
Feb 15: Chung Yik Tin is released after the Obscene Articles Tribunal finds that the photo he was arrested for publishing should have been classified as "indecent" - a lesser offence.
Feb 17: Edison Chen's expected press conference does not happen. Gillian Chung performs for the first time since the scandal on broadcaster TVB's charity show. The broadcasting watchdog receives more than 1,900 complaints against her appearance.
Feb 18: Apple Daily says an underworld figure has offered HK$500,000 (S$90,400) for Edison Chen's hand to be chopped off.
Feb 21: Chen returns to Hong Kong and says he will quit the Hong Kong entertainment industry.