Raymond and Thomas Kwok were arrested last week by Hong Kong's Independent Commission Against Corruption (ICAC) in the agency's biggest investigation since it was set up in 1974 to root out graft in the government and police.

"I can tell you definitely that I personally do not do anything wrong and I believe that Thomas Kwok has done nothing wrong," Raymond Kwok told reporters as the pair faced the media at the company's headquarters in Hong Kong's busy Wan Chai district.

The brothers, worth $18.3 billion according to Forbes magazine, said the investigation would not affect business decisions at Asia's largest developer, and that sales and development plans would go ahead as scheduled.

The company owns some of the former British colony's largest properties, including its tallest building, the International Commerce Centre that houses Morgan Stanley and the Ritz Carlton.

The arrests last Thursday of the two brothers, along with Rafael Hui, a former No. 2 official in the Hong Kong government, came days after the election of Beijing-loyalist Leung Chun-ying as the city's next leader, pledged to address soaring property prices.

The Hong Kong public has been increasingly aggrieved at the perceived cosy ties between government and big business, and some observers have interpreted the arrests as a first move in an attempt to rein in the power of the monied elite.

The brothers and Hui were released on bail and have not been charged with any offence.

But last week's event dented investor confidence and nearly $5 billion in Sun Hung Kai's market value was wiped out when trading in the company's shares resumed on Friday.

On Tuesday the stock rose about 2 percent to around HK$96.25, still well below HK$111.10 when the company halted trading in its shares last Thursday. The benchmark Hong Kong share index .HSI closed up 1.3 percent.

Sun Hung Kai is a family-run conglomerate, founded by the Kwok's father, and owns phone, trash and bus businesses in Hong Kong.

In the past few weeks, Sun Hung Kai has also disclosed that Thomas Chan Kui-yuen, in charge of project planning and land acquisitions, had been arrested for suspected bribery.

The Kwok family had a public feud in 2008 that ended with elder brother Walter being ousted as chairman. Thomas and Raymond, backed by their mother, claimed Walter was mentally unfit to run the business, claims Walter has denied.

Walter Kwok alleged in a 2008 writ trying to prevent his ouster that he had concerns about the way the company was being run, including doubts about a land acquisition in Hong Kong's rural New Territories, the way the firm granted construction contracts and questions about a lease at their tallest building, the International Commerce Centre on the Kowloon peninsula.

(Additional reporting by Denny Thomas, Michelle Chen and Twinnie Siu; Editing by Chris Lewis and Alex Richardson)

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