Another three men and a woman have been arrested for possessing obscene photos depicting what appear to be local entertainers.

Speaking on a radio talk show today, Commissioner of Police Tang King-shing said the four were arrested early this morning at various locations.

Initial investigations found the arrestees know each other but have no connection with the 29-year-old man who has been charged over the online publication of the obscene photos.

Mr Tang said officers are working to stop the circulation of the photos with the help of Internet service providers and overseas law enforcement agencies.

On speeding, the commissioner reiterated Police have directed laser gun operators to follow the manufacturer's procedures and will form a working group to review training and use of the devices.

Officers will also collect information from the drivers who asked for a review of their speeding cases to decide if their requests are justified.