Rai Sikandar, with the ministry of electricity and water, said a malfunction was reported at a privately run thermal power plant in southwest Pakistan that pressured all major power-producing systems, which eventually shut down, Khaama Press reported.
The nationwide blackout began about 11:30 p.m., local time, Sunday after the plant in Balochistan province stopped generating electricity, officials said.
"The [Hub Power Co.] plant developed a fault and the load was transferred to the Mangla and Tarbela [power plants] but they tripped [went offline]," Javed Parvez, chief executive officer with Islamabad Electric Supply Co., said. "After that, several smaller powerhouses tripped."
Dozens of cities across Pakistan including Karachi, Hyderabad, Nawabsha, Peshawar, Quetta, Lahore, Multan, Rawalpindi and Islamabad were affected by the two power houses going offline, Geo TV News reported.
Blackouts are common in Pakistan because of chronic power shortages, Khaama Press said.