KARACHI, Pakistan -- Nearly 150 people have died from heatstroke in the southern Pakistani port City of Karachi in the last two days, officials said Monday.

Hospital reports confirm at least 148 deaths, said the city's health director, Zafar Ejaz.

Hundreds more are being treated for heat-related ailments, including fever and dehydration, said Seemi Jamali, a spokeswoman for Jinnah Hospital. She added that most of the deaths have been among elderly people.

Karachi has been in the grip of a rare heat wave, with temperatures soaring to 45 degrees Celsius (113 degrees Fahrenheit). A collapse of the local power grid over the weekend made matters worse.

The heat wave is the worst in at least a decade, but the arrival of monsoon rains in the coming days should bring relief, meteorologist Mohammad Hanif said.

Health officials have advised people to stay out of the sun and drink more fluids.(AP)