BEIJING (Reuters) - Xu Ming, a former business ally of disgraced Chinese politician Bo Xilai, has died in prison of illness, local media reported on Sunday (Dec 6). He was 44.

The founder of plastics-to-property conglomerate Dalian Shide Group died on Dec 4, according to the news websites of Tencent, China's biggest social network, and Hong Kong's Phoenix television.

Xu had heart problems and died at a penitentiary in Wuhan in central Hubei province, the Tencent website reported, quoting a former company executive.

The trial of Xu, listed by Forbes as China's eighth-richest person in 2005, had been shrouded in secrecy. It was never made public when he was arrested, indicted and convicted. His prison term was unknown.

Xu was scheduled to be released from prison in September 2016, Phoenix television said.

Xu's relationship with Bo became a focus a few years ago when the politician was probed for corruption.

Bo was ousted as Communist Party boss of the south-western metropolis of Chongqing and from the party's decision-making Politburo in 2012. He was sentenced to life in prison in 2013 for corruption and abuse of power.

During Bo's trial in 2013, the court said Bo was charged with receiving about 21.8 million yuan (S$4.76 million) in bribes from Xu.

During the trial of Bo's wife, Gu Kailai, for murdering a British businessman, Gu said she had asked Xu to pay for a villa in France.

Xu's friends and relatives accompanied his coffin to his hometown in the north-eastern port city of Dalian on Sunday, according to Phoenix.

Xu's kin could not be immediately reached for comment.