But health chief urges people not to panic because the insects do not present a risk on the scale of Sars Red fire ants might have been in Hong Kong for some time and could be impossible to eradicate, the health chief said yesterday, as the number of suspected anthills surged to 126. Chek Lap Kok airport and the Sheung Yue River in Sheung Shui became the latest suspected habitats of the ants, following the Hong Kong Wetland Park in Tin Shui Wai and Yeung Uk Tsuen in Yuen Long. The Agriculture, Fisheries and Conservation Department will launch an investigation into the relationship between at least 126 colonies identified during the past three days to see if the plan to control the ants should be adjusted. An interdepartmental taskforce led by the Health, Welfare and Food Bureau has also been set up to co-ordinate patrol efforts by various departments which will report findings to the agriculture department. Secretary for Health, Welfare and Food York Chow Yat-ngok said the ants might settle in Hong Kong permanently. 'I cannot rule out this possibility ... they might have been in Hong Kong for some time. But we need to study more to confirm this,' he said. Chief Executive Tung Chee-hwa last night said officers would step up inspections and co-operation with Guangdong on the ants. 'For me and our administration, the health of the public is of the utmost importance,' he said. Agriculture department deputy director Lau Sin-pang said 12 anthills had been found and destroyed on a slope at East Coast Road on the eastern tip of the airport island after a report from Airport Authority officers on Thursday. The authority has urgently requested its pest control contractor to inspect the whole airport island and destroy any anthills, if found, in five days. A further 30 anthills were found in a new green area managed by the government on the Sheung Yue River. The number of mounds found at the wetland park also jumped by 28 to 68 while 10 more anthills were located near Yeung Uk Tsuen yesterday, bringing the total to 16. Most of the anthills have been destroyed except five in the Sheung Yue River area, where inspection and pesticide spraying will continue today. 'We still have little idea on the distribution of the anthills right now,' Mr Lau said. 'What we will do is to input the anthill data and locations we have into the geographic information system to study their distribution and density. By doing so, we hope to find out if there is a relationship between the places the anthills are found so that we can see if our control strategy should be adjusted.' He said the department will focus on areas with newly planted vegetation. At a flower nursery in Tai Po yesterday, Dr Chow said that as the ants could fly, they could spread to other places although they could be confined to rural areas. 'According to the experts, the chance [of finding the ants] is low in urban area as the ants need spacious land to breed,' he said. Dr Chow urged the public not to overreact, saying the ants were just insects, not a virus such as Sars. Meanwhile, Guangdong vice-governor Tang Bingquan claimed the spread of the ants - thought to have come from the mainland in imported plants - was under control in the province and his officials would liaise with Hong Kong on the issue.