Chan denied prosecution allegations that he was part of an "elaborate disguise" to help the company's co-chairmen, Thomas Kwok Ping-kwong and Raymond Kwok Ping-luen, bribe Hui to the tune of millions of dollars between 2005 and 2009 to be their "eyes and ears" in the government.

The family rift was apparent in Raymond Kwok's 2001 diary, parts of which Thomas Kwok's lawyer read out concerning their older brother, Walter Kwok Ping-sheung.

"Walter Kwok gone crazy", "he's sick", "he cannot trust anyone", "he has a splitting character" and "his face can change quickly" were among the words the youngest brother penned in his diary, Mr Justice Andrew Macrae and the nine jurors heard.

Chan agreed to all the descriptions except the one about Walter Kwok being "crazy". Rather, he said he would describe him as "not the person he used to be".

Walter Kwok wanted to make "extremely risky investments everywhere in the world", each involving tens of billions of dollars, the court heard.

"The two brothers said to me, if their older brother continued to act like that, it would be possible that the company might have to wind up," Chan said, without specifying when the comment was made. Walter Kwok was ousted as chairman in 2008.

Chan also testified about his own investment in AlcolOut, a medicine said to prevent hangovers.

Having heard from Hui that Francis Kwan Hung-sang was "very reliable", Chan paid Kwan HK$12 million in 2007 to invest in the drug, which Kwan said could generate an annual profit of up to HK$50 million after it entered the mainland market.

"How do you feel now you know that your money was paid over to Mr Hui, who spent it on high living," Chan's lawyer, Ian Winter QC, asked.

Chan replied: "I'm very disappointed. I'm agitated and angry."

He had "no knowledge at all" - until the court trial - that Kwan, Hui's childhood friend, had channelled his money to Hui.

He said he had "made it clear" to Kwan: "Do not move my money now. Before you make any investment, tell me about that. And only do it after you have my consent."

Hui's lawyer, Edwin Choy Wai-bond, asked why Chan did not keep track of how his money was used. "I suggest to you although you're a very rich man, HK$12 million was still a sizeable sum," the lawyer said.

Chan replied: "Actually, there's no way for me to keep track of that." He said the sum was meant to buy Kwan's shares in AlcolOut.

The prosecution is to cross-examine Chan from today.

Hui, 66, faces eight charges related to bribery and misconduct in public office. Thomas Kwok, 63, faces one charge of conspiracy to offer an advantage to Hui and two counts of conspiracy to commit misconduct in public office. Raymond Kwok, 61, faces four charges, including one with Hui of furnishing false information. Chan and former Hong Kong stock exchange official Kwan, 63, each face two charges.

All have pleaded not guilty.

Blockbuster graft trial: the first 100 days

The five defendants in Hong Kong's most high-profile graft trial deny all charges of bribery, misconduct in public office and furnishing false information. Ex-chief secretary Rafael Hui Si-yan is accused of taking HK$34 million in cash, loans and other inducements between 2000 and 2009 from Sun Hung Kai Properties co-chairmen, brothers Thomas Kwok Ping-kwong and Raymond Kwok Ping-luen, partly via alleged middlemen SHKP executive director Thomas Chan Kui-yuen and former stock exchange senior executive Francis Kwan Hung-sang, who is Hui's childhood friend.

A juror quits complaining of illness, leading Mr Justice Andrew Macrae to discharge all eight remaining jurors.

Second jury, comprising six women and three men, is empanelled.

Start of lead prosecutor David Perry QC's four-day opening statement, alleging how the Kwoks bribed Hui via an "elaborate disguise" to be SHKP's "inside man" and "eyes and ears" in government. Statement claims Hui lived a "lavish" lifestyle that cost up to 10 times his income, and passed inside information about West Kowloon Cultural District and Ma Wan developments to the Kwoks.

Bank records show Hui's debts rose from HK$4 million to HK$57 million in the two years after his term as chief secretary ended in 2007. Hui had a taste for keeping horses, five-star hotel meals, trips abroad and opera, making him "an obvious target for exploitation".

Hui begins his defence testimony, describing himself as someone who would spend everything in his pockets and pay only minimum charges on credit card bills. He spent HK$200,000 in a single day in 2007 on musical recordings.

Hui, married since 1974, says he lavished millions on a young Shanghai woman with whom he had an "intimate" relationship that lasted for two to three years from 2008.

Hui admits evading taxes on income totalling HK$21.8 million, earned from Thomas Kwok, in the years before and during his term as chief secretary.

Hui reveals secretly receiving HK$11 million "from Beijing" in 2007 and offers of help from top mainland official Liao Hui .

Thomas Kwok begins defence testimony, describing how he negotiated brother Walter Kwok Ping-sheung's release from abductor "Big Spender" Cheung Tsz-keung in 1997.

Trial enters its 100th day. It was due to have ended this month, based on the original 70-day schedule.

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