I am the original poster. It seems like training centers such as Keyword are being targeted by the police or immigration officials for hiring illegal workers, which are people without the proper Z-Visa and work permit. The situation at these training centers, and maybe other schools as well, is getting intense. Foreign teachers are being told to literally go back to their home country after flying all the way to China only to have their work permits and residence permits DENIED. Some training centers are still hiring people illegally, people with tourist, student, business, or other non-work visas are told they can come teach English. Simply trying to transfer your work permit to another job is also a complicated process. For a long time people could work on the wrong visa in China, but now China is enforcing the policy more in big cities.

True but many of those Chinese get a lot of help from their educational system and local authorities' suggestions-"Be careful when you see a foreigner!"

Lets face it Chinese for the most part do not trust or like foreigners.

This is happening all over china to include Beijing. They've been coming around using portable bio-metrics readers as well. Why bother working there in the first place unless you can't find a job as an educator in your country? Pollution, corrupt schools, censorship, human rights violations, human trafficking, massive fraud in illegal school transcripts and visa fraud at consulates involving schools promising parents that their children are guaranteed to pass, etc. If you are black and in China, multiply that by 100. Expect to be visited by plain clothes immigration police soon and carry your passport at all times. They've been doing massive residential checks, employment checks, and checks on mass transit too. By the way the foreign expert card belongs to you and not your employer. Make certain you have it on you and the school has a copy of it.

As an added plus, if you are married to a Chinese spouse and they have been issued a green card from your own country, you cannot enter China on a family visa to go see them if they're back in China. You'll need another family member to write you an invitation letter in order to get the family visa good for ten-years with a 120 day stay period per visit. If you have an R or a Z visa already, fine.

Also if you get your spouse a green card from your own country, the Chinese government is now cancelling their family registry books. Check with any police station and they'll tell you to your face. That means they lose all social insurance benefits and basically everything. They're still Chinese, but have no rights.

If you have a Chinese PR card, and I do, its of little or no value other than you don't need a work visa. That card, and 8 RMB still buys a cup of coffee at KFC. Be prepared to be delayed longer at checkpoints as most cops never saw one and don't have experience in clearing them. In Shanghai its easier as most of them were issued there.

People cannot be "illegal". Their behavior, possessions, even communication can be illegal, but not themselves. There is no law against existence.
Undocumented foreigners. Foreigners who have entered or remain in the country illegally.