Millionaire Li Haicang, who was murdered in his Shanxi office on Wednesday, was a 'long-time acquaintance' of the suspected killer, a government spokesman said yesterday. Authorities were working to establish whether it was a murder-suicide, or whether other people were involved, the Shanxi government official said. The spokesman said the family of 47-year-old Feng Yinliang, whose body was also found in Li's office, was now 'under close surveillance'. Li and Feng were the same age and they came from the same village, the spokesman said. However, he declined to comment on reports that Feng's wife was being detained on charges of illegally possessing firearms and that their two children had also been arrested. He also declined to comment on a Shanxi Daily report which said Feng, boss of a now-defunct paper mill, was involved in a dispute with Li over a land deal. According to China News Service, the debt-ridden Feng had suffered heavy losses on the stock market. The murder of the mainland's 27th richest man shocked the nation and prompted the central leadership to order 'a thorough investigation', according to the spokesman. He said police had recovered five bullets fired at the scene. The spokesman said the bullets were of the same calibre and a five-shot homemade rifle had been recovered at the scene. A report on the China News Service Web site said Beijing forensics experts had been sent to Shanxi to assist in the investigation. The Public Security Ministry declined to confirm the claim yesterday. Li was the boss of the Haixin Group, the second largest steel manufacturer in China after Taiyuan Steelworks. Li's employees held a ceremony yesterday afternoon at company headquarters in Wenxi to pay tribute to their slain boss, a staff member said. Taking advantage of the local coal resources to fuel his furnaces, Li built Haixin into a leading steel business with sales in 2001 of US$360 million (HK$2.8 billion), paying taxes of US$11 million. The company has 7,300 employees. Haixin has diversified into the real estate and finance sectors. Starting out as a town and village enterprise, the company is now privately owned. Li was a member of the Chinese People's Political Consultative Conference and a vice-chairman of the All-China Federation of Industry and Commerce, China's top body representing the business sector.