More than 2 million affected by monsoon flooding in India

The prime minister of India toured the country's flood-ravaged northern region on Thursday where more than two million people have been displaced or stranded, declaring the situation a "national calamity and unprecedented."

Manmohan Singh announced his government would provide 10 billion rupees, or around $228 million US to the northern state of Bihar and released 125,000 metric tonnes of food grains.

The death toll in Bihar from the floods rose by 12 on Thursday to 47, according to the Indian government's national disaster management website.

Meanwhile, emergency officials are still struggling to reach those affected by the latest floods and contain a river breach in the state.

Air force helicopters continued to drop food and supplies to flood-ravaged areas, while government workers helped soldiers sandbag the bank of the Kosi river.

The river has changed course since the Aug. 18 breach, further inundating surrounding districts with floodwater and sweeping away villages, roads and rail lines.

Situation 'extremely grim': UNICEF

Government agencies have already removed more than 150,000 people from the affected region, while many times more have moved out on their own to higher ground and safer areas, said Mukesh Puri, an emergency officer for UNICEF.

"The situation is extremely grim," Puri told CBC News on Thursday from the state's capital, Patna.

Meanwhile, relief agencies are concerned about infectious diseases spreading among the hundreds of thousands crowded into relief camps amid scarce provisions of clean drinking water and poor sanitation conditions, he said.

"People are using stagnant water, and if it is not purified, it could lead to some serious implications," Puri said.

More than 1,600 people have already died as a result of this year's monsoon season, which began in May and is expected to end in September.