The flood toll in Assam has crossed 66 as heavy rains batter the Northeast, officials said. Nearly 700 villages are underwater across the state. In Dima Hasao district, nearly 200,000 people have been cut off as roads and bridges were blocked by landslides or washed away. Several railway stations were closed because of flooding. The Army has deployed helicopters for rescue work. Four people were killed in neighbouring Arunachal Pradesh after heavy rain and mudslides. Two died when their houses on a hillock collapsed in Itanagar, and two road construction workers were killed by mudslides at another site. Seven more deaths were reported in Assam. The weather department has forecast very heavy to extremely heavy rain in the region for the next four days. Landslides and floods are common in the Himalayan north, and scientists say they are growing more frequent with global warming. Relief camps are sheltering displaced families across the worst-hit districts.