Beijing is clean, safe and less populated these days. And Chinese authorities are certainly serious about security of the Olympics. The following information in Chinese blogosphere may give us a clue on how this is being done, translated by CDT:
An announcement poster that was photographed in Tangshan's north railway station in Hebei Province:
According to requirements of the Fengrun District People's Government of Tangshan City, in order to guarantee security for the Beijing Olympic Games and directives from superior government agencies, from 8:00 on July 21, 2008 to 8:00 on September 30, those citizens from this district who need to take the train out of Tangshan north station must produce their ID card and an introduction letter (介绍信) from their neighborhood committee, residential area or employer to buy a ticket.
Everyone please obey the aforementioned rules when buying tickets. The railway agency will not be held accountable for any consequences of disobeying these rules. Thank you for your cooperation.
Also in a blog post on Netease, someone writes about their experience of being unable to return to Beijing without proper ID:
So we were returning to Beijing from Datan and had to take a coach bus from Fengning County seat. A local driver purchased six tickets for us. Although the Olympics had put a tense atmosphere over the whole country, we didn't think about it too seriously. Even with the Games, people still have to eat, sleep, go to the toilet and travel around. We were returning to Beijing, not to make trouble there.
But we were still asked for our ID and got our card numbers recorded. Although Fu Guoli lost his ID card, he is a gentleman-faced guy and works for a Global 500 company and we couldn't imagine he would have a problem.
Fengning town was in total darkness. I told "Little Orange," in order to secure water and power sufficiency in Beijing, there were outages of running water and electricity in many parts of Hebei. "Little Orange" took it as a joke, and I couldn't prove it with solid facts.
When the bus pulled out of town, I was sitting next to Fu Guoli and while we were chatting the bus pulled over. When we walked off the bus we first saw cops, who set up two checkpoints along the highway and two policemen in bullet-proof vests with light machine guns were minding the booths. We were submitting our ID cards one after another along a rail line. For those who have the second generation of IDs, a scan can tell whether it's real or fake; but for those first generation ones, your information needs to be entered into a computer and then a matching program will confirm its authenticity.
I passed without any problem. But Fu Guoli showed his work badge and reported his ID number, seemingly not much a hassle, but was taken aside by the cops. From 1:00 to 1:20 am, I saw through the bus window that he was constantly talking to the cops and was not allowed to board, and we realized something was wrong.
Just then, when Fu gave them his ID number, the computer couldn't find his record, and neither could the system find his name. Which is to say, the police concluded that Fu has no valid ID record, which means he couldn't be allowed back to Beijing.
He was, finally, left behind with police at Fengning, not able to return to Beijing.
Some words from the cops:
"As long as the system shows your record, your ID is fake to us even though it's real; if the system doesn't have your record, your ID is real even though it's a fake one. It's just that simple."
"You and him are two different person. What kind of qualification do you have in order to guarantee him [as a good civilian]?"
"Even it is the problem of the database, it is still your problem. We still cannot let you go!"