A scorching heat wave across southern Pakistan's city of Karachi has killed at least 436 people, authorities said Tuesday. Temperatures reaching 45 degrees Celsius (113 degrees Fahrenheit) began roasting Pakistan's port city of Karachi over the weekend. Hourslong power outages also struck the city, leaving fans and air conditioners inoperable. The power outages also affected the sporadic water supply in the city, AP reported. Most of the dead are the elderly, said Seemi Jamali, a spokeswoman for Karachi's Jinnah Hospital. Thousands more are being treated for heat-related ailments, including fever and dehydration and stomach-related illnesses, she said.