Rumors have circulated since last March that mining tycoon Liu Han had disappeared.

Liu was elected political adviser in Sichuan province three times in a row and has more than 20 honorary titles. His best-known charitable act was the building of a rural elementary school complex that withstood the devastating 2008 Sichuan earthquake.

He is chairman of the board of Hanlong Group, the biggest private enterprise in Sichuan, and of the listed Jinlu Group. He owns subsidiary companies involved in electricity, energy, finance, mining, real estate and securities. Estimates put his worth in the tens of billions of yuan.

The Ministry of Public Security ordered police in Beijing, Hubei and Sichuan to investigate Liu in March last year, and bring to justice the alleged leader of a Mafia-style criminal group.

The news of the prosecutions has sent tremors through Sichuan's political and business circles.

Liu's case first attracted attention with a murder case on Jan 10, 2009, in Guanghan, Sichuan. At an open-air teahouse in the downtown area, several men got out of a car, fired at least 10 shots and killed three people before escaping in the same car. Two pedestrians were injured.

The two suspects, Yuan Shaolin and Zhang Donghua, were soon captured and named Liu Wei, Liu Han's brother, as the mastermind of the killing. By then, Liu Wei had already absconded and became the most wanted man by police.

Liu Wei was boss of Guanghan Yiyuan Industrial Corp and a popular entrepreneur and philanthropist; and even a torchbearer for the Beijing Olympics in August 2008.

However, to those who knew him, Liu Wei was a ruthless underworld kingpin who controlled gambling, loan sharking and construction projects. Chen Fuwei, one of the men slain in the teahouse, was Liu's sworn enemy.

The police received tips on Liu Wei's whereabouts from time to time in the ensuing four years, but he slipped away each time, thanks to his big brother, Liu Han, they said.

Liu Han was born in 1965. In the early 1990s, he and Liu Wei ran gambling centers in Guanghan. At that time, the brothers mustered a gang of local thugs and vagrants.

In 1993, they openly broke a seal on properties that had been seized by the court and used guns against law enforcers. The same year, Liu Han fraudulently obtained a loan that he used to do business before his fortune began to accumulate.

In 1998, one of Liu Han's companies waded into a real estate development project in Mianyang, Sichuan's second-largest city. After a confrontation with villagers over demolition compensation, Tang Xianbing, a security guard with Liu Han's company, stabbed and killed Xiong Wei, the leader of the protesters.

"Nothing happened to me after the killing, and that made me bolder and more unscrupulous," Tang later confessed to police. "I would do anything for the company, even murder. I was fearless."

Silenced by the murder, the villagers made way for the property project.

Five days after the killing of Xiong Wei, Liu Han ordered Zeng Jianjun, one of his henchmen, to kill rival gang boss Zhou Zheng in Guanghan, according to the authorities.

In February 1999, Wang Yongcheng, another gang boss in Mianyang, threatened to blow up Liu Han's company building.

Days later, Wang was gunned down by a shooter allegedly sent by one of Liu Han's lackeys, Sun Huajun.

In September 2000, Liu Wei instructed his men to kill Liang Shiqi, an old neighbor whose aunt had raised Liu Han as her own, authorities said. Liu Wei allegedly ordered the killing out of a suspicion that Liang had pocketed his "dog minding fees".

In May 2002, Liu Han's bodyguards Qiu Defeng and Huan Lizhu provoked a brawl in a recreation center in Chengdu, capital of Sichuan. One person was killed and many injured.

Qiu was later sentenced to four years in prison. The other killers walked free.

Liu Han was soon established as a "kingpin" in Guanghan and Mianyang. Some of his victims were forced to leave their homes in fear of his gang.

More than 100 members of the public were made to suffer by the group, the authorities said.

In 2008, Chen Fuwei, boss of another Guanghan gang, was released from prison, threatening to take revenge on the Liu brothers. In response, Liu Wei allegedly called in Wen Xiangzhuo and Kuang Xiaoping and told them to "get rid of Chen".

The killing took place in broad daylight on Jan 10, 2009.

Afterward, Liu Han allegedly arranged for Liu Wei to escape and lobbied for his innocence. Liu Han met with his younger brother many times since then, giving him millions of yuan.

Evidence collected in the investigation show Liu Han's gang involved in dozens of serious criminal offenses, including homicides, assaults and illegal detentions, over more than 10 years. There have been at least nine deaths, five of which were the result of gunfire.