The first winter ice has appeared on the Yellow River in northern China a few weeks earlier than normal. State television broadcast footage of the drifting ice that had started to form on a section of the river in Hequ county in Shanxi province on Thursday. CCTV said the ice began to form at the end of last week, which is about a fortnight earlier than in previous years because of a cold snap that hit the region. Hequ is normally the first place in Shanxi where the river freezes. Ice has also been seen further upstream in Inner Mongolia and Qinghai provinces, with a 139km section of the river being reported to have frozen in the former alone. According to water conservancy authorities in Hequ, no ice dams have yet formed and the ice is still drifting slowly and steadily. Local authorities have set up nine observation sites to monitor the situation and have warned people to take extra care along the river banks. Dams form when the ice becomes backed up in narrow sections of the river, which increases the risk of flooding as water levels rise. Ice formation on the river is an annual occurrence and it is usually frozen over between mid-December and late February.