Electricity was restored to most of Pakistan on Monday after a nationwide blackout that sparked stone-throwing protests and even fuelled rumours of a coup attempt, officials and witnesses said.
The outage on Sunday, the country's worst in five years, blacked out almost the whole country including the major cities of Islamabad, Karachi and Lahore for around four hours and overnight in some areas.
"Electricity has been fully restored in the country," Shafqat Jalil, general manager of public relations for the Water and Power Development Authority, told the agency.
Losses to businesses were estimated at 200 million rupees (3.3 million dollars), he added.
Officials blamed a technical fault and said there was no hint of "sabotage or an act of terrorism".
Newspaper reports blamed a short circuit in a major distribution line but the authority said the cause was not yet known.
But many parts of Pakistan, which has a population of 150 million, remained without electricity overnight and supplies were still patchy in some parts on Monday, witnesses said.
In Karachi, Pakistan's biggest city, the situation "has not returned to normal and power supply has not been restored in several areas," said Salahuddin Haider, a spokesman for the government of Sindh province.
Witnesses said people in Karachi's Liaquatabad area burned tyres and pelted vehicles and complaint centres of the local electricity company with stones late Sunday.
Thousands of people remained at the city's Clifton beach until late in the night due to the heat and the lack of air conditioning.
Meanwhile the sheer scale of the blackout helped to fuel rumours of an attempted coup against President Pervez Musharraf while he was away in the United States.
Musharraf said Monday in New York that the rumours were "absolute nonsense", according to the official Associated Press of Pakistan.