Several cities and towns across Pakistan plunged into darkness late on Saturday night following a huge blackout due to a fault in the power distribution system, according to media reports.
The power outage was reported shortly before midnight almost simultaneously in many cities. Residents of Karachi, Rawalpindi, Lahore, Islamabad, Multan and others faced the blackout, the reports stated.
Islamabad Deputy Commissioner Hamza Shafqaat tweeted that the National Transmission Despatch Company's lines have tripped, causing outage. "It will take sometime before everything gets back to normal," he added.
Power Minister Omar Ayub Khan said the frequency in the power distribution system suddenly dropped from 50 to zero, causing the blackout. "We are trying to ascertain what caused the drop in frequency, Ayub said.
Initial reports suggest there was a fault in the Guddu power plant in Sindh province at 11.41 pm, the Energy Ministry tweeted.
The fault tripped the high transmission lines and this resulted in the system frequency to drop from 50 to zero in less than a second, causing power plants to shut down, according to the ministry.
It added that Khan was overseeing the restoration work at the National Power Control Center.
The minister appealed to people to maintain restraint and said power restoration was being carried out with caution and teams were on the ground.
Later, Khan posted a series of tweets regarding restoration of power in several grids.