Her online post was quickly transferred to all major Chinese forums. Hours later the girl received a phone call from the emergency headquarter, asking for more detailed description. Ultimately her information helped the air force to find its way into Wenchuan.

Shortly after the quake, as Wenchuan turned inaccessible, posts looking for missing or unreachable relatives there appeared on popular online communities like Baidu Tieba and Tianya.cn. These communities soon set up special message boards dedicated for users to find relatives or friends in the quake-hit areas and to seek help in case of emergency. Even irrelevant strangers often clicked into these post boards to leave messages of blessings and encouragement.

Google China also launched a tool which enables users to search people information in various BBS, so anxious users do not need to check each main BBS to find their loved ones.

As rescue and relief efforts in the quake-hit areas became the top concern of most Chinese over the past 10 days, the Internet offered a platform for people to share all information and follow up the latest developments. Apart from reports from the news media, on-the-scene accounts, pictures and video clips from survivors, eyewitnesses, volunteers and other ordinary citizens were also frequently uploaded to the Web through blogging or podcasting.

"Chinese Internet users have become a major force in spreading information. They can complement to the organizational holes and fill up the vacuum. They've played an important role in communications in the rescue work," said Yu Guoming, president of the Media Research Institute at the Beijing-based Renmin University of China.

Another Beijing media expert who asked not to be identified added that the participation of the Internet users helped cover some blind spots of the news media, giving a further push to the trend of information transparency and public supervision.

In a latest typical example, Internet users in Chengdu, the provincial capital of Sichuan, exposed a possible scandal of some Chengdu residents' alleged misappropriation of tents prepared for homeless survivors in the quake-razed towns and villages.

Seeing media reports based on tips from the Internet users, the Chinese authorities have pledged immediate probe into the case and severe punishment for those found guilty.

The Internet also served as a main channel for the Chinese to mourn for the quake dead and convey condolences to their families. Almost all main Web portals opened message boards for users to offer prayers and blessings, and more than 650,000 people had left their prayers on Sina.com's Webpage alone as of May 23.