The number of dead had earlier been estimated to be over 200, but Farooq Sattar, who has served as the mayor of Karachi and currently sits in the country's parliament, told IRIN the governor of Sindh Province - of which Karachi is the capital - and the mayor had been able to verify only 66 names from hospitals as being storm-related deaths.
The roofs of houses collapsed, mostly in the city's slums. Falling signboards and power cables that electrocuted some people added to the death toll.
"We are now making a concerted and coordinated effort to help the affected," Sattar said.
People had been moved from low-lying areas to "safer places like schools, and temporary aid camps had been set up to provide assistance, with food relief a top priority", he added.
Tropical cyclone on the way?
Meanwhile, the country's top meteorologist warned of more rains along Pakistan's coastal areas.
"Very heavy rain is expected in the next 24 hours," Qamar-uz-Zaman, who heads the Pakistan Meteorological Office, said, adding that a tropical cyclone could hit the coast by the late evening of 25 June.
This is expected to be a major concern for an already beleaguered city administration which has been reeling from rioting by incensed citizens protesting at frequent power cuts in the sweltering summer heat. More people came out onto the streets on 24 June after being forced to spend the night without electricity.
Sattar said strict conditions for future installations of advertising hoardings - most of which were uprooted by winds exceeding 60 knots on 23 June - had now been drawn up to help mitigate the effects of future storms.
"Administration in a city of this scale is always going to be a problem and this thunderstorm and heavy rain has exposed the difficulties. But we are trying to find the best way to deal with the problem and find solutions so that it doesn't happen again in future," he said.
According to the UN Development Programme, Pakistan, due to its diverse terrain, is susceptible to droughts, floods, earthquakes and cyclones. A major drought has been continuing for four years in varying degrees all over the country. In addition, most years the country suffers from flooding as monsoon rains cause rivers to burst their banks.