Seven people were killed and 19 others, including eight Taiwanese, were injured when a huge boulder rolled down a mountainside in south China's Guangxi Zhuang region on Thursday morning.Four people were confirmed dead at the scene, and three others were declared dead after being rushed to hospital after the incident occurred at around 9 a.m in Guilin city, Xinhua news agency reported. A tourist group was visiting the site at the time.The eight Taiwanese, all slightly injured, were being treated at a local hospital.Guilin is famous for its mountainous landscape, with soluble rocks on the mountains prone to landslips, residents said. Visitors are cautioned against landslips at the site where the incident occurred.