People cover themselves during a dust storm on a hot day in Prayagraj, India, on Sunday. AP
The deaths occurred in three districts of the poor northern state, where temperatures have hovered around 45˚C in recent days, senior health official Vijay Kumar told AFP.
Forty-nine people died in three districts of the Magadh region that has been hit by drought, he said.
"It was a sudden development on Saturday afternoon. People affected by heatstroke were rushed to different hospitals," Kumar added.
"Most of them died on Saturday night and some on Sunday morning during treatment."
Kumar said about 40 more people were being treated at a government-run hospital in Aurangabad.
"Patients affected by heat stroke are still being brought, the death toll is likely to increase if the heatwave continues."
Indian women collect drinking water at a well in Nawargawa village, Madhya Pradesh state, on Sunday. AFP
Most of the victims were aged above 50 and were rushed to hospitals in semi-conscious state with symptoms of high fever, diarrhoea and vomiting.
Twenty-seven people died in Aurangabad district, 15 in Gaya and seven in Nawada district, officials said.
State Chief Minister Nitish Kumar has announced a compensation of Rs400,000 ($5,700) for the family of each victim.
People cover themselves as they walk during a dust storm on a hot day in Prayagraj, India, on Sunday. AP
Harsh Vardhan, India's health minister, said people should not leave their homes until temperatures fall.
"Intense heat affects brain and leads to various health issues," he said.
Large parts of northern India have endured more than two weeks of sweltering heat. Temperatures have risen above 50˚C in the desert state of Rajasthan.
A heatwave in 2015 left more than 3,500 dead in India and Pakistan.
In 2017, researchers said South Asia, which is home to one fifth of the world's population, could see heat levels rise to unsurvivable levels by the end of the century if no action is taken on global warming.
India typically witnesses water scarcity during summer months, but the situation this year is particularly bad in western and southern states which received less than normal rainfall in the 2018 monsoon season.
As if the political heat, accompanied by clashes and protests, claiming lives in some parts of India were not enough, the searing heatwave in India has also taken over the role of the Grim Reaper, hitting alarming levels. Four people died in ‘unbearable’ heat while travelling by train in northern India,
India is the fifth most vulnerable of 181 countries to the effects of climate change, with its poorest being the most at risk, according to the Global Climate Risk 2020 report.
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