Accidents happen on the Internet from time to time. This time the trigger was a video. A Chinese couple, videotaped hugging and kissing on a subway platform in Shanghai, plan to sue the subway's operator after the video was uploaded to YouTube and other video-sharing websites, attracting thousands of hits.

Talking can be heard in the background of the video, in which one man is requested to adjust the angle of the camera to shoot the couple better. It is suspected that the uploader might be among the staff of the subway company who worked at the camera monitoring office.

Greatly embarrassed, the couple has hired a lawyer in the interests "of all passengers traveling on subway trains in Shanghai," claimed the unnamed man in the video. "Now every time I walk into a subway station I feel uncomfortable," he added.

The subway's operator, Shanghai Metro Operation Co. Ltd., claimed that it would pay much attention to this issue and promised "severe punishment" if employees were found to have given away the video.

On the Internet, the video scandal has caused much controversy. Outraged netizens accused the uploaders of breaking professional ethics. They said the scandal has spread a feeling of insecurity among people in public places monitored by cameras.

Other voices are saying that the couple should have been more disciplined and paid attention to their own behavior.

Shanghai subway authorities later apologized to the couple and dismissed an employee involved in uploading the video.

An internal investigation found people who worked for the Shanghai metro uploaded the video. Shanghai Metro Operation Co. Ltd. is negotiating with the couple over compensation.

After the investigation, three members of staff were found accountable for capturing and uploading the video footage. Two of them had already left the company in September last year. The other one, a female, was dismissed after the incident caused public uproar. The subway company also said it would enhance internal management and ethics education.

Cameras are widely used in public venues, such as subways, supermarkets, convenience stores, banks, roads, lifts, hospitals, mainly for ensuring security and tracking down criminals. Even companies have installed cameras inside their offices.

But there have been worries about whether the cameras infringe on privacy and if companies can properly protect the video data from being released to the public. Chinese legal experts and scholars have called for more robust privacy legislation to regulate the use of video footage and impose penalties on its abuse.

Earlier this year, northeast China's Changchun City, Jilin Province, invested 140 million ($19 million) to install some 20,000 cameras, dubbed "electric eyes," in key positions around the city. These "electric eyes" have proved a good way to save human resources and increase efficiency, and are also a deterrent to criminals and an aid to the police, according to the city authorities.

The monitoring system is supposed to safeguard public security, said law professor Gao Fuping with the East China University of Political Science and Law in Shanghai. The use, storage and management of video data should be under strict control and used by the judicial and public security departments only under certain procedures, said Gao.

A worry is that many video-sharing websites are keen to provide provocative and private videos to cater to viewers eager for novelty; therefore attracting more hits and making more profits from advertisements.

Videos that infringe on the privacy of ordinary people can be spread so fast and widely through the Internet that the effect can be devastating. However, there is little effective supervision and management of the contents of these websites, according to experts.

The management of Internet audio-visual programs is likely to improve soon after a regulation issued by the country's broadcasting, film, TV and information industry authorities took effect on January 31. The regulation said online videos should not insult or slander others, or infringe upon privacy.

"The regulation will have a positive impact on the current situation of video-sharing websites," said Chinese expert on Internet and information Zhou Binqing. He also acknowledged that there will be difficulties in deciding who should appraise videos and how.