China’s richest man, an electronics tycoon worth more than £4 billion, has disappeared, amid reports that he is under investigation for alleged insider trading.

Huang Guangyu, 39, who turned a single street stall selling radios and watches into China’s largest electrical appliance chain, has not been heard of for several days, according to his company. Mr Huang vanished last Wednesday and the absence of information about his fate highlights the opacity of China’s justice system and the secrecy with which the police routinely conduct their investigations.

Reports slipped out at the weekend in Caijing, an unusually hard-hitting business magazine, which said that the billionaire was in trouble. By yesterday trading in shares of Mr Huang’s Gome Electrical Appliance Holdings had been halted on the Hong Kong stock exchange. The company issued a statement saying that it was making “necessary inquiries” to try to find out what had happened to its founder and controlling shareholder.

One source close to Gome – a household name in China as the cheapest and most reliable source of everything from kettles to flat-screen televisions – said that Mr Huang appeared to be incommunicado. No government department had contacted the company about his whereabouts and no notice had been received about any legal investigation into its activities.

“It’s business as usual. The CEO, Chen Xiao, is in charge and telling suppliers that everything is under control,” said the source.

Known as “the Price Butcher” for the discounts available at his stores, Mr Huang has always been vulnerable in a system in which connections count for more than business clout.

Many of China’s self-made tycoons avoid the limelight, aware that their prominence could trigger retribution from officials who are jealous of their meteoric rise to prosperity.

Caijing reported that Gome’s chairman was being questioned by police for alleged share-price manipulation linked to Shandong Jintai Group, a drug manufacturer listed in Shanghai that is believed to be controlled by his brother, Huang Junqin.

Trading in the financially troubled company was suspended in Shanghai on Monday. Caijing said that the share price of Jintai had fluctuated for most of the past two years, but it did not specify how Huang Guangyu may have been involved.

A devout Christian from the southern port city of Shantou – known in the 19th century as the British treaty port of Swatow – Mr Huang topped China’s Hurun Rich List this year with wealth estimated at $6.3 billion (£4.2 billion), from his shares in Gome and his growing property empire.

It is not the first time that Mr Huang has faced questioning. He was investigated in late 2006, along with his brother, for alleged financial irregularities involving the use of a loan to speculate in real estate. Both brothers were released and cleared of any charges in January 2007.

The mystery surrounding his latest disappearance deepened when even Xinhua, the state-owned news agency, was unable to get a comment from the police. A police official said only that the issue was being handled by the Ministry of Public Security – an indication that Mr Huang’s fate now lies with the highest decision-makers.

Gome’s business has been booming. Its results for the third quarter, released yesterday, showed that net profits soared 111 per cent in the first nine months of 2008 to 1.59 billion yuan (£155 million).

Several former rich list celebrities have run foul of the law, typically over financial misconduct. Zhou Zhengyi, the eleventh-richest person in China in 2002 and the boss of Nongkai Group, was sentenced to 16 years in jail in 2007 for bribery, embezzlement and tax fraud.

Zhang Rongkun, the sixteenth-richest in 2005 and the owner of Fuxi Investment, was sentenced to 19 years in jail in June for his role in a billion-dollar pension fund scandal in Shanghai. “People attract more attention from the public once they get listed,” said Ren Jianming, an expert on corruption issues at Tsing-hua University in Beijing. “Maybe other rich people who aren’t on the list also did business in ways that probably did not comply with the laws, but they may get less attention.”

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