Over 1,200 people have died in Pakistan's Sindh province due to a heat wave described as the worst in decades, as major hospitals in the country's largest city struggled to cope with the unprecedented influx of patients seeking treatment for heatstroke-related illness.

The death toll in worst-hit Karachi, Sindh's provincial capital, has reached 1,000, with more than 200 people reported dead in other parts of the province.

Anwar Kazmi of Edhi Foundation, which runs the largest ambulance service in the region, told PTI that death toll in Karachi, a metropolis of over 18 million people, has reached 1,000.

"At least 1,000 have been killed in Karachi only. I do not have data of rest of Sindh province but there are reports of deaths," he said. Sindh Chief Minister

Qaim Ali Shah said that more than 200 have died in the interior areas of Sindh due to the intense heat wave. Sindh government has declared public holiday today in a bid to keep people indoors away from the heat.