HONG KONG, Aug 2 (AP) -- Two Chinese men have admitted they tried to steal the remains of the wife of Asia's second-richest man to blackmail him, newspapers reported Wednesday.

The two defendants, Liu Huihuang, 36, and his elder brother Liu Huizhi, 42, admitted in a Hong Kong court Tuesday that they joined six others in an attempt to rob the grave of Chong Yuet-ming, the late wife of Hong Kong tycoon Li Ka-shing, in January 2006, Hong Kong newspaper Ming Pao Daily News reported.

The Liu brothers also admitted attacking the cemetery's caretaker, robbing him and his wife of HK$50,000 (US$6,387; £á4,680) in cash, a gold necklace and two mobile phones, Ming Pao said.

The grave robbers damaged Chong's tomb but didn't leave with her remains, the Apple Daily said.

The Lius, who were not immediately sentenced, face a maximum penalty of 10 years for blackmail and causing criminal damages, and life imprisonment for robbery.

Judiciary spokeswoman Jaime Or couldn't confirm the guilty pleas.

In earlier testimony to police, Liu Huihuang said the mastermind behind the crime was from Hong Kong and had hired the two brothers in September 2005, Ming Pao said. It wasn't immediately clear if the mastermind has been arrested.

Spokeswoman Laura Cheung at Li's conglomerate Hutchison Whampoa said the businessman had no comment.

Li, a Buddhist, said earlier the tomb raiders would suffer bad karma and would lack peace for the remainder of their lives.

Li's wife died in the 1980s, according to The Standard newspaper.

Li was ranked Asia's second-richest individual -- after steel magnate Lakshmi N. Mittal _ and ninth overall by Forbes magazine this year, with a net worth of US$23 billion (£á16.8 billion).