Forty people, mostly homeless, died over the past 24 hours in the impoverished Indian states of Uttar Pradesh and Bihar, state officials said.
The chilly weather has claimed at least 41 lives in the past fortnight in the Himalayan Kingdom of Nepal, state radio said.
Bangladesh's Independent newspaper said on Sunday that 368 people had died in the last month, mostly in the north. More fatalaties in Uttar Pradesh, Bihar and another Indian state, Rajasthan, brings the total to more than 740.
Uttar Pradesh weather official R.K. Verma said cold conditions were aggravated by fresh snowfall in the Himalayas and several flights and trains had been cancelled.
Weather officials said the cold spell with thick fog would last for a few more days.
The official Bangladesh news agency said the current cold spell was the worst since 1968.
Officials in the Indian states of Uttar Pradesh and Bihar said schools were likely to remain closed for a few more days.
"We will review the situation on Monday and the closure may be extended for a couple of more days," said Deepak Prasad, district magistrate of Bihar's capital Patna where the mercury dipped to 4.6 degree Celsius.
Although not cold by the standards of many other nations, the drop in temperature can have a devastating effect on the hundreds of thousands of homeless people in the three countries.
- Reuters - Thomson Reuters Foundation
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