Power supply has been restored in many parts of Pakistan by Sunday afternoon, Energy Minister Omar Ayub Khan said.

The services were restored fully or partially in many cities, including Islamabad, Rawalpindi, Lahore, Multan, Karachi and Faisalabad, but it would take some time before the situation returned to normal across the country, the minister said in a series of tweets.

The nationwide blackout began at 11:45 p.m. on Saturday in all major cities of Pakistan, including Karachi, Islamabad, Lahore, Peshawar, and Rawalpindi.

More than 200 million people were left without power, which was gradually being restored to major cities across Pakistan early Sunday.

The frequency drop resulted from a fault at Guddu at 11:41 p.m, according to Pakistan’s Energy Ministry.