ISLAMABAD (NYTIMES) - At least 65 people have died in recent days from a suffocating heatwave that has afflicted Karachi, Pakistan's sprawling southern port metropolis, the charitable foundation that runs the city's central morgue said on Monday (May 21).

Government officials did not confirm the figure but exhorted residents of Karachi, a city of 15 million, to take precautions because of the heat.

Faisal Edhi, a member of the family that runs the Edhi Foundation, which runs an ambulance service and Karachi's central morgue, said that of the 160 bodies received in the past three days, 65 were of people who had died because of the heatwave.

On Monday, a temperature of 44 degrees Celsius was recorded in Karachi, which often is referred to as a concrete jungle because it lacks large areas of plants or trees. In recent years, heatwaves have claimed hundreds of lives.

Last week, the Pakistan Meteorological Department issued a heatwave alert for Karachi, warning that the maximum temperature this week would range between 40 and 43 deg C with no respite from sea breezes.

The Karachi authorities have urged people to stay indoors this week and keep themselves hydrated. Frequent power failures have compounded the misery.

The heatwave coincides with Ramadan, the Muslim holy month when Muslims fast from sunrise to sunset.

Most of the dead were from the working-class neighbourhoods of Korangi and Landhi, Edhi said, and included older men, women and children.

In 2015, at least 1,000 people died in Karachi from a heatwave that paralysed day-to-day life and overwhelmed the health care system.

Pakistan has endured a persistent increase in temperatures in recent years. Last month, the temperature reached 50.2 deg C in Nawabshah, a city in southern Sindh province. Weather experts said that was the highest temperature recorded anywhere in the world in April.