ISLAMABAD, Pakistan — At least 65 people have died in recent days from a suffocating heat wave that has afflicted Karachi, Pakistan’s sprawling southern port metropolis, the charitable foundation that runs the city’s central morgue said Monday.

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 leads the Edhi Foundation, which runs an ambulance service and Karachi’s central morgue, said in an interview that of the 160 bodies received in the past three days, 65 were of people who had died because of the heat wave.