Story highlights The heat wave has killed over 1,000 people in Karachi and Sindh province

At least 650 bodies have been brought to Karachi's largest morgue since Saturday

One Karachi hospital has treated more than 7,000 people in the past four days

Karachi, Pakistan (CNN) The unforgiving heat has spared no one. The very young, the very old and those in the prime of their lives.

Corpses covered in flies lie outside city morgues. Inside, bodies up on bodies are piled high.

Hospitals are overwhelmed, relying on volunteers and donors for ice, water and even spare beds.

By Thursday, the death toll from the oppressive heat wave in Sindh province topped 1,000, officials told CNN.

But even without the numbers, the full extent of the misery isn't hard to gauge.

Photos: Pakistan's deadly heat wave Covered corpses from a devastating heat wave lie in a mortuary in Karachi, Pakistan, on June 26. The death toll from the heat wave in Sindh province topped 1,000, officials told CNN. Hide Caption 1 of 13 Photos: Pakistan's deadly heat wave A Pakistani child pours water on his cattle to cool off during a hot afternoon in Peshawar on Thursday, June 25. Hide Caption 2 of 13 Photos: Pakistan's deadly heat wave Pakistanis bring a heatstroke victim to a hospital in Karachi on Thursday, June 25. More than 1,000 people have died in a heat wave in southern Pakistan, officials say. Hide Caption 3 of 13 Photos: Pakistan's deadly heat wave A patient suffering from heatstroke receives treatment at a Karachi hospital on Wednesday, June 24. Hide Caption 4 of 13 Photos: Pakistan's deadly heat wave Pakistanis receive ice during the heat wave in Karachi on June 24. Hide Caption 5 of 13 Photos: Pakistan's deadly heat wave A man awaits medical help for his daughter who is suffering from dehydration due to the extreme weather in Karachi on June 24. Hide Caption 6 of 13 Photos: Pakistan's deadly heat wave A man helps move a heat wave victim to a Karachi hospital on Monday, June 22. Hide Caption 7 of 13 Photos: Pakistan's deadly heat wave Pakistanis rest at the mosque during the heat wave in Karachi on June 22. Hide Caption 8 of 13 Photos: Pakistan's deadly heat wave A Pakistani man cools down at a mosque during the heat wave in Karachi on June 22. Hide Caption 9 of 13 Photos: Pakistan's deadly heat wave A Pakistani man rests at a mosque during the heat wave in Karachi on June 22. Hide Caption 10 of 13 Photos: Pakistan's deadly heat wave Pakistani volunteers and relatives prepare to shift the bodies of heat wave victims into the cold storage of the Edhi morgue in Karachi on June 22. Hide Caption 11 of 13 Photos: Pakistan's deadly heat wave Pakistanis cool off at a river outside Islamabad on Sunday, June 21. Hide Caption 12 of 13 Photos: Pakistan's deadly heat wave Relatives mourn the death of a heat wave victim at the Edhi morgue in Karachi on June 21. Hide Caption 13 of 13