Dongguan, in the heart of the Pearl River Delta, has more than 8 million permanent residents, but only 1.87 million of them are locals with household registrations, sources within the local government said.

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Dongguan 'remains processing trade hub'

"Booming manufacturing attracted millions of workers from all over the country and has helped make it one of the foreign trade leaders in China since the country's opening-up and reform," Lin said.

Xinhua News Agency cited Yao Kong, the city's deputy Party chief, as saying that 10 percent of the world's sneakers are produced in Dongguan, about 20 percent of the world wears Dongguan sweaters and 30 percent of the world's children play with Dongguan toys.

World-famous electronic brands, such as Nokia Oyj and Samsung Co Ltd, have also built plants in the city.

However, Xiao Feng, deputy general manager of Shenzhen Onetouch Business Service Co, said Dongguan's economy, which relies heavily on foreign trade, faces a big challenge in the years ahead after overseas demand started to fall and labor and production costs squeezed profits for local businesses.

"The export-oriented businesses should be upgraded with more technology and innovation. Otherwise manufacturers in Dongguan will find it hard to boost their competitiveness in the global market," Xiao told China Daily.

Local authorities have attached growing importance to upgrading the manufacturing industry by encouraging businesses to focus more on innovation and technology since the 2008 financial crisis, says Xian Zhou'en, director of the Dongguan Economy and Information Bureau.

Exports of high-tech products from the city rose to $33.6 billion last year, an increase of a little more than 13 percent year-on-year, representing an increased proportion of all exports, according to Xian.

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