Guangzhou has long dreamed of being considered an international city - but events last month at a downtown police station were not quite what leaders had in mind. Furious when they thought a Nigerian clothes trader had died, more than 200 Africans dragged the body to the station in Kuangquan district and started a siege. For four hours they vented their fury at officers and onlookers, smashed plants and trees, and forced traffic on a busy road to grind to a halt. The protest, believed to be the first by a group of foreigners anywhere on the mainland, was the boiling over of long-standing frustrations with visa policies among the city's sizeable African community. Emmanuel Okoro fell from a second-storey window of a market when he attempted to flee a visa check on July 15. His fellow traders filmed him with blood pouring from his head and assumed he was dead, but police later said he was still alive and being treated in the intensive care unit of a local hospital. The incident was a reminder of the huge challenges that internationalisation will bring Guangzhou. The city is home to the mainland's largest African enclave. Authorities said in May that there were only 20,000 foreigners of all nationalities - but this is a major underestimate. Local media puts the number of Africans alone at up to 100,000. Many work in the markets around Xiaobei district - known to irreverent locals as 'Chocolate City'. It cuts an incongruous sight in a mainland metropolis - with English and Arabic signs instead of Chinese, and streets full of Africans. Many make money as traders cashing in on ultra-cheap products directly from the doorstep of the 'world's factory', but others struggle to make ends meet and find low-paying work as porters or cooks. Overstaying is a major problem. An official report said the number of overstayers had risen from about 2,400 in 2001 to more than 6,300 in 2005, an average annual increase of 40 per cent. And these, of course, are just the ones that get caught; on the afternoon Mr Okoro was injured, police chased three other African traders. One was caught when he injured himself jumping out a window, but the other two escaped. Officials warn that the increasing number of overstaying foreigners - mostly Africans and Southeast Asians - has led to crimes such as robbery, fraud and smuggling. There is also the problem of drug dealing. A couple of years ago a group of provincial consultants proposed that Guangdong should only welcome foreigners who are 'experts, hi-tech professionals and investors'. 'It is impossible for Africans who want to do basic labour work in Guangdong because we already have great employment pressure,' one of the consultants who drafted the proposal told the South China Morning Post. The Africans, however, say unfair visa policies are the problem - not them. Many are given only one-month visas, which they say is not nearly long enough to conduct business. Increasingly tight visa policies across the country mean very few are able to get extensions. Guangzhou police would not comment on whether their policies are stricter than in other cities, but a Malian clothes trader said it was easier to get an extension in Beijing and Shanghai than in Guangzhou. Those who are committed to staying must contemplate more creative approaches. A Nigerian trader named Ike said he was planning to marry his girlfriend, a Chinese trader in the same market. 'My family will agree to me doing so, and I want to stay in Guangzhou after the wedding instead of going back home,' he said. The tough visa policies towards Africans hardly fit in with the mainland's broader strategy towards the continent. Sino-African friendship has been a national policy since the Mao Zedong era. The continent is at the heart of the mainland's energy and resources strategy, and trade in recent years has boomed. The central government will not be keen to jeopardise this through more stories of impossible visa policies and Africans with blood gushing from their heads. Just as Africans are forced to find new ways to stay, so Guangzhou will have to find new ways to deal with them. It is just that there isn't a lot of precedent - for centuries, Guangzhou was a hub of emigration, not immigration. That many are now flocking to Guangzhou in search of wealth is a sign the city is well on track to becoming an 'international' city - but sometimes you have to be careful of what you wish for.