KARACHI - A heat wave has killed more than 400 people in Pakistan's southern city of Karachi over the past three days, health officials said on Tuesday, as they set up emergency medical camps in the streets.The heat wave coincides with major power cuts, leading to harsh criticism of the provincial government and K-electric , the company that supplies electricity to Karachi, the country's richest city and home to 20 million people.One of Karachi's biggest public hospitals said all its beds were full, with more than 200 people dying there of dehydration or heat exhaustion."Some were brought in dead, while others died during treatment," said Dr Seemin Jamali, joint director at Jinnah Postgraduate Medical Centre.Civil Hospital was also full of heatstroke patients. A few old fans blew the sweltering air past stray cats sprawled in the dark corridors as friends of an unconscious policeman rushed outside to buy him the cold water the hospital could not provide."This is how it is. No one cares for common poor man here," Khadim Ali complained as he fanned his cousin, Shahad Ali, a 40-year-old vegetable vendor who collapsed in the heat.Temperatures have touched 44 degrees Celsius (111 degrees Fahrenheit) in the steamy port city in recent days, up from a normal summer temperature of 37 C (99 F). But rain is due.