The army has deployed helicopters to assist in the rescue operation.
Four people were killed in heavy rains and landslides in the border state of Arunachal Pradesh on Monday, officials said. Two more were killed when their house collapsed on a small hill in the state capital, Itanagar, and two road construction workers were killed in a landslide elsewhere.
Seven more deaths have been reported in neighboring Assam. About 700 grams of water is under water, according to the state Disaster Management Agency.
The Indian Meteorological Department has forecast heavy to very heavy rains in the region for the next four days.
Landslides and floods are common in the northern Himalayas of India. Scientists say they are becoming more frequent because global warming contributes to melting glaciers there.
In 2020, flash floods killed nearly 200 people and washed away homes in the state of Uttarakhand. Thousands died in the 2013 floods.