Heavy rain in the entire Himalayan region have triggered floods in Assam and Bihar. The northeastern state has been the worst hit - 15 people have died in the last four days and nearly 23 lakh have been displaced. The rail link to northeast India from the rest of the country has been severed. Water levels in the Brahmaputra and several other rivers are still rising, hitting train services. National Highway 37 is flooded, cutting off upper Assam from the rest of the state. Over 80 per cent of Assam's Kaziranga National Park, home to one-horned rhinos in India, has been flooded.