He is not alone - more than 1 million fellow migrants have lost their homes since the city government started demolishing slums and squatter areas in February.

The campaign, a pet project of Mayor Li Hongzhong , is unprecedented in its scale. In less than five months, authorities have demolished a floor area of more than 30,000 sq km - roughly the size of a small mainland city.

The crackdown sparked outrage and earned Mr Li the nickname of 'Tough Man Mayor'.

In June, an anonymous writer published an article headlined 'Shenzhen under the Bronze Statues [of Deng Xiaoping ]' on the internet. The article hit out at the demolition campaign and Mr Li's administration.

The article accused the Shenzhen government of seeking superficial improvements at the expense of hundreds of thousands of underprivileged people.

Most of the people affected by the campaign were migrant workers from rural areas in inland provinces. They had always struggled to earn a living in the city and could not afford accommodation outside slums and squatter areas.

The author said the demolition campaign had destroyed thousands of families, had thrown the helpless onto the streets and could have disastrous consequences. The article sent shockwaves through Shenzhen and left Mayor Li and his colleagues red-faced.

'He [the mayor] was infuriated, particularly because the author claimed to have sent several copies to the central government,' said a government source.

Before the campaign was launched, President Hu Jintao and Premier Wen Jiabao repeatedly stressed the importance of even development and caring for the country's poor.

Shenzhen authorities ordered the article to be removed from the internet and responded to the allegations on the front page of the city's largest newspaper, the Shenzhen Special Zone News.

'Mayor Li should not be blamed. He is only trying to solve problems left by previous administrations,' said Yang Lixun , a scholar with the Shenzhen Academy of Social Sciences think-tank.

'The spread of squatter villages in Shenzhen had reached a stage where they would ruin our future if we didn't do something about them.'

Shenzhen was just a village 25 years ago and has undergone one of the most dramatic urbanisation processes in the country's history. Every day, thousands of migrant workers arrive seeking to improve their lives, creating a huge market for illegal guesthouses and the underground rental market.

The native farmers saw an opportunity to cash in and turned their farmland into makeshift squatter areas to accommodate the new arrivals.

'At first, the government let each native family build a three-storey building over 40 square metres of land for their own use. But virtually no one followed that order. They just built wherever they wanted and the buildings are getting taller and taller,' said Professor Yang.

'Previous governments turned a blind eye. When Mayor Li entered office earlier this year, the problem had reached a stage where it required urgent action.'

Shenzhen now has a permanent population of 2 million with residential permits, but the total population is estimated at 10 million. The most conservative estimates put the population of migrant workers at 5 million.

Squatter areas have not only become an eyesore but have also created huge social problems. Authorities say more than 90 per cent of the city's crimes take place in squatter villages.

Brothels, underground casinos, illegal clinics and drug-trafficking centres have also flourished. Most of the buildings are poorly built, making them vulnerable to fires and typhoons.

Compounding the problem is the fact that Shenzhen is running out of useable land. Shenzhen Party Secretary Huang Liman admitted last year that the city would use up its land reserves within a decade or so.

This has eroded the city's competitiveness. Professor Yang said many foreign multinationals had abandoned their investment plans for Shenzhen due to a lack of suitable land.

'Suzhou and Guangzhou have outstripped us in economic development. These two cities have merged with neighbouring towns in the past decade and they are now four times bigger than us. Shenzhen has not added one inch of land,' he said.

With plans for mergers with Huizhou and Dongguan scuttled, the Shenzhen government turned its attention to the squatter villages.

Many middle-class residents have applauded the demolition campaign, saying it has given the city a drastic facelift and improved security.

'In the past, the first impression that outsiders got of Shenzhen was that it was chaotic, unsafe and dirty,' said insurance saleswoman Veronica Zhang, whose property in Gangxia, Futian district, shot up 15 per cent in value after a nearby squatter area was torn down.

'Now the environment has been improved a lot.'

But across the street in a slum, Hunan migrant Wang Li cursed the government.

'I worked day and night for this city. Now it has no use for us and wants to boot us out. Shenzhen officials care only about money, they have no heart,' said the former factory worker who lost his job when his plant was relocated to Huizhou .

The campaign has led to a number of violent conflicts between residents and officials in recent months and the controversy looks set to continue, with the local government announcing a new round of demolitions last Wednesday.

The government is a long way from declaring victory in its battle, however, as new tin-and-timber buildings often reappear several days after others are torn down.

'While some old squatter villages are torn down, many new villages are under construction,' said one resident.