Mainland police are offering a reward of up to 200,000 yuan (HK$187,600) to track down the killers of a Hong Kong-listed company vice-president and his family in Fujian. Hengan International Group of Companies vice-president Wu Shijie, 49, his wife and two daughters were found tied and gagged at his company dormitory where they lived in Anhai town, Jinjiang city, on Monday. Initial reports suggested all windows at the scene were closed and the gas was turned on. The victims had suffocated. Wu's son died in a car accident last year. His daughter-in-law was said to have returned to her home a few days before the murders. Investigators believed there were at least two or three killers. The group's Hong Kong office said it was shocked and saddened by the death of Wu who was also one of the company's directors. It said the company had contacted Wu's family members and would assist in co-ordinating the funeral. While mainland officers believed the murders could be linked to financial matters, the company would not comment any further. 'The death of Mr Wu Shijie will not cause material effect to the company's normal operation,' the company said. Wu, who joined the group when it was founded in 1985, owned 24.3 million shares, which closed yesterday at $2.95. Hengan International manufactures and sells personal hygiene products such as sanitary napkins and disposable baby diapers, mainly in China. Police were said to have met all of the staff in Jinjiang on Tuesday night. The murders have alarmed leaders in Fujian, where a special investigation team comprising officers from the city, county and provincial levels has been set up. Public security bureau chiefs in Jinjiang and the deputy mayor have inspected the murder scene. An officer from the city's public security bureau said: 'We are offering a reward of between 50,000 and 200,000 yuan to anyone who can provide information leading to the detection of the case.'