Story highlights The heat wave has killed 800 in Karachi and 38 elsewhere in Sindh province, official says

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) At the Edhi morgue in Karachi, the smell is overwhelming.

At least 650 bodies have been brought here since Saturday. Many lie in storage. But an oppressive heat wave -- and the frequent power outages from electricity grids trying to keep up with demand -- means the morgue is unable to properly maintain the temperature at the overcrowded facility.

A handwritten sign outside says the morgue is filled to capacity. Other bodies lie outside.

A sign in Urdu dated from Monday announced that The Edhi Morgue, the largest in the city of #Karachi is full. Bodies are still coming in, the majority of them being victims of the ongoing heat wave. The smell is overwhelming. The morgue is running on a generator and bodies are piled in layers of three. #KarachiHeatWave A photo posted by Sophia Saifi (@sophiasaifi) on Jun 23, 2015 at 10:04pm PDT

Such is the state of affairs in the beleaguered seaport city of Karachi. A record-breaking heat wave has killed 800 in the city and 38 others elsewhere in Sindh province, according to the chairman of Pakistan's National Disaster Management Agency, Gen. Asghar Nawaz. Authorities fear the toll will only rise.

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