Chinese new exit and entry law came into effect July 1, completing the country's first major overhaul of border regulations in more than two decades.

For the first time, foreigners can be detained for five to 15 days if they're caught illegally living or working in China.Illegal migrants can now be fined 5,000 yuan (US$794) to 20,000 yuan and face deportation under the new law. Their employers could be fined up to 100,000 yuan per individual illegal employee.

Some 47,100 foreigners were caught violating the immigration law in 2012, according to data released by the Ministry of Public Security earlier 2013.

The new law also aims to reform the green card system, which since 2004 has allowed foreigners to permanently reside on the mainland. By the end of 2011, only 4,752 people had been granted green cards.

The new law also promises more convenience for foreigners coming to China to work, with the introduction of a "talent introduction visa." Overseas candidates with management experience at leading multinationals and top specialists in education and science are eligible to apply for a talent visa in China."Urgently needed" professionals, as stated in the law, will be able to apply for the new talent visa, which grants residency for up to five years, or multiple entries and stays of up to 180 days at a time.

The new law states that the minimum stay for foreigners holding work permits will be 90 days, while the period of validity for a residence permit will range from 180 days to five years. Foreigners who commit "severe violations" that do not constitute crimes may be deported and not allowed to enter the country again for 10 years.

The law also states that exit-entry authorities must set up passages exclusively for Chinese citizens and promulgates regulations to collect fingerprints or other biometric data from people entering and exiting the country.

About 594,000 foreigners live in China, according to the 2010 national census. Most come from South Korea, the United States and Japan. Last year, 54.35 million foreigners entered and exited China, 37 times the amount in 1980.