Public security officials yesterday released more than 50 people who were detained after attempting to organise a National Day protest in Tiananmen Square against corrupt land planning officials. Officials denied anyone had been arrested, but Guan Zhenli, one of the organisers, said he had been held since September 30. 'They told me to stop participating in politics,' said Mr Guan, a social activist who has helped various Beijing residents organise protests against forced evictions by local district governments. 'I told them I am a laobaixin [an ordinary resident], but that I hoped the government would abide by the law and stop cheating us.' More than 1,000 people tried to converge on the capital on October 1 to protest against corruption among land development and urban planning officials, but cancelled the demonstration after their leaders were arrested. It is widely believed that local urban planning officials pay only 30 to 40 per cent of the money for land development they receive from developers to evicted residents and pocket the rest. The corruption in China's real estate sector is now so serious that President Hu Jintao mentioned the issue in a recent speech. Nicholas Becquelin, research director of Human Rights in China's office in Hong Kong, said he believed top officials were so concerned about the severity of corruption that they may have intervened to ensure those arrested were treated leniently. 'One of the reasons authorities are not adopting a very hard punishment is these people are well grounded in their complaints,' Mr Becquelin said. 'They also have worked hard not to do anything illegal.' Protesting without official permission is illegal on the mainland, he said, 'but the police are allowing some small-scale protests'. But small-scale illegal protests in minor neighbourhoods and larger ones in Tiananmen Square are two different issues. Just 10 days ago, a man set himself ablaze in protest at being evicted from a Beijing neighbourhood. The incident, covered by the international media, was a huge embarrassment to the central government. 'Most of these people receive small amounts of money and many are now homeless because they can't afford to buy new homes with the money they receive,' Mr Guan said. 'They cheat us and then they won't let us protest.' Mr Guan said he would organise a petition drive among recently evicted Beijing residents to protest against government harassment. Liu Wei, a spokesman for the Beijing Public Security Bureau, denied any protest organisers were detained. 'I never heard of such a thing,' he said. By only temporarily detaining the protest organisers, Mr Becquelin said central authorities were tacitly allowing minor protests to take place. 'It is seen as a way to rein in local authorities,' he said. But he said if the government was serious, it would allow residents to file class-action lawsuits against agencies or officials.