Three days after two of Hong Kong's richest tycoons and a former top government official were arrested on suspicion of corruption by the ICAC, the government has broken its silence on the unprecedented probe, describing it as an 'individual incident' that will not affect the morale of the civil service. With the chairmen of property giant Sun Hung Kai, Thomas Kwok Ping-kwong, 60, and his brother Raymond Kwok Ping-luen, 58, along with former chief secretary Rafael Hui Si-yan, 62, all out on bail following their arrest, a senior official yesterday responded to questions on the Independent Commission Against Corruption investigation that has rocked the city. Secretary for constitutional and mainland affairs Raymond Tam Chi-yuen described the arrest of Hui - who masterminded outgoing leader Donald Tsang Yam-kuen's re-election campaign - as 'an individual incident'. He added: 'I do not believe the incident will affect the morale of civil servants.' No one has been charged in connection with the probe as yet, but the arrests in connection with allegations of bribery and misconduct in public office have been interpreted by some as an attack on the city's influential property tycoons. It is understood the ICAC's investigation was given fresh impetus by the forced departure of Walter Kwok Ping-sheung, the older brother of the Sun Hung Kai chairmen. As revealed by the South China Morning Post, he spoke to anti-graft agents prior to his brothers' arrests, following a bitter family feud three years ago. In the past, Walter Kwok, who was forced by his siblings to leave the company in 2008, has made unsubstantiated allegations regarding executive director Thomas Chan Kui-yuen, the Sun Hung Kai land acquisition boss who is also on bail after being arrested earlier this month in connection with the same probe. Claims of collusion have intensified the debate over 'developer hegemony', in which property developers are accused of maximising their influence by building up land banks and dominating business in various sectors, according to Lawrence Poon Wing-cheung, an estate specialist teaching at the City University. 'The arrest will reinforce public discontent against the developer tycoons,' he said. 'In the past, developers have been known for manoeuvring the grey areas in flat sales. Now they are proved to have offended laws in order to reap more profits.' According to Sun Hung Kai, the company has built up a total of 26 million square feet of agricultural land, the second-largest land bank in the New Territories following Henderson Land's. Sixty-nine per cent of the gross floor area it is developing is in the New Territories. Yip Siu-chau, a retired schoolteacher living in Mei Foo Sun Chuen, said the arrest corroborated suspicions of collusion. 'It wouldn't be made public if the Kwok siblings were not fighting against each other,' he said. 'I do think there are a lot of bribes happening between the government and the business sector. They were not revealed because investigation is difficult.' Yip is a resident affected by a New World Development project. The company stands accused of constructing a high-rise that might block the airflow and sunlight of Mei Foo residents despite not having full ownership of the site. Meanwhile, last night, the Hong Kong Press Photographers Association said a Cable TV cameraman sustained neck injuries when scuffles broke out between reporters and security guards at the entrance to Sun Hung Kai's headquarters in Wan Chai. The fracas erupted when a group of reporters attempted to film a vehicle, believed to be carrying Raymond Kwok Ping-luen, as it entered the headquarters.