Islamabad – Most of Pakistan, including the capital and many of its major cities, lost electricity early Sunday in one of the biggest blackouts affecting this country of more than 200 million people.

It was not immediately clear why. Initial reports stated that the collapse was tracked at a power station in the southern province of Sindh that ultimately affected the entire transportation system. Officials said emergency efforts were being made to restore the electricity, but it was not immediately clear when that would be.

The blackout affected the capital, Islamabad, along with major cities such as Lahore, Karachi, Peshawar and Quetta. Electricity was returned to parts of the capital early Sunday morning.

The country was plagued by chronic transmission system problems, and major power outages were frequent.

In January 2019, problems at the Judo Thermal Power Plant led to a main power outage in the Sindh and Baluchistan provinces. In May 2018, a widespread collapse in the Northern System of the National Transportation and Control Corporation caused people to lose power in Punjab and Khyber Pakhtunkhwa.

Eighty percent of the country lost Power in 2015 When Baloch separatists attacked the transmission line.

On Sunday, officials urged the public to remain calm and discredited the speculation on social media.