Beijing, April 20 (Inditop.com) Over 6,000 people, including 31 foreigners, have been arrested in Shanghai ahead of an international expo for their alleged involvement in theft, pornography and prostitution.

Police launched a 12-day crackdown in an effort to make Shanghai city safer during the upcoming international expo to be held from May 1.

More than 30,000 police officers conducted around 900 raids and arrested 6,402 people on various charges, China Daily said Tuesday quoting the Shanghai public security bureau.

These include at least 31 foreigners who were caught for being in the country illegally, using drugs and being employed in an illegal hotel in Minhang district, police said.

At least 429 people are under criminal detention on charges of theft, gambling, prostitution and selling pornographic materials, while 852 people are under administrative detention, facing a maximum term of 15 days, officials said.

The others were released after being “educated”, according to the statement.

Police also focused on traffic offences, street crimes and potential fire hazards in and around the expo area. More than 2,000 unlicensed two wheelers were confiscated.