Tens of thousands of people take shelter in relief camps as heavy rains batter India’s northeast

Nearly 14,000 people in shelter homes across 20 districts of Assam

Flood-affected people transport cattle in Nalbari district in the northeastern Indian state of Assam (AP)

One person died and tens of thousands of people moved to government shelters as heavy monsoon rains batter villages in India's northeastern state of Assam.

At least 500,000 people are reeling under the deluge across 12 districts of Assam, which have been put on red alert to brace for more bouts of rain this weekend.

Nearly 14,000 people are in 83 relief camps run by the Assam government in 20 out of the state's 31 districts, said the disaster management agency in a statement.

"We are fully prepared to deal with the situation with our rescue agencies deployed at vulnerable and worst-affected locations," said GD Tripathi, a state government official.

One person died due to flooding in Udalguri district, the state government said, adding it was the first official record of death on account of flood this year.

According to reports, the Nalbari district in western Assam had the highest number of displaced people at 3,816.

Most of the designated relief camps have been submerged due to the incessant rains forcing authorities to make make-shift arrangements on embankments and roads.

People were seen wading through knee-high and at times waist-high water levels to shift their cattle and other belongings.

One of Asia's largest rivers, the Brahmaputra, floods annually. It flows 800 miles across Assam before running through Bangladesh, which shares a 160-mile border with Assam.

Apart from the Brahmaputra, the Beki, Manas, Pagladiya, and Puthimari rivers were also reportedly flowing above the danger mark at several stretches.

A man carries his livestock as he wades through flood water in Rangia, in India's Assam state (AFP via Getty Images)

Annual monsoon rains hit the region in June-September. The rains are crucial for crops planted during the season but often cause extensive damage.

Mudslides triggered by heavy rains have occurred in several parts of Assam and Sikkim states, the government said.

The National Disaster Response Force (NDRF), State Disaster Response Force (SDRF) with fire services have been pressed into the rescue operation. At least 19 boats have been deployed across six districts and 561 people have been rescued so far.

Flood affected villagers sit under a temporary shelter during rainfall in a flood affected area in Morigaon district of Assam (EPA)

In neighbouring Meghalaya state, a mudslide demolished a boundary wall of a large sports stadium, damaging several vehicles parked there.

Last year floods in India and Bangladesh left more than a dozen dead and millions homeless.

The pattern of monsoons has been shifting since the 1950s, with longer dry spells interspersed with heavy rain, according to Roxy Mathew Koll, a climate scientist at the Indian Institute of Tropical Meteorology in Pune.

Scientists say climate change is a factor behind the erratic rains that trigger unprecedented floods in Bangladesh and north-eastern India, killing dozens and making lives miserable for millions of others.

With agency inputs.