ISLAMABAD –A blackout hit Pakistan Sunday, leaving 80 percent of the country without electricity.

Zafaryab Khan, a spokesman for the Ministry of Water and Power, said the blackout was due to a militant attack.

The attack on a transmission tower in southwestern Baluchistan created a power surge, creating the worst blackout in Pakistan’s history—leaving over 140 million citizens without power.

Emergency protocols were put into place to partially restore the capital, Islamabad, and Karachi, the most populous city.

The attack to the power grid further reinforces the vulnerability of Pakistan’s power grid. Since Jan. 13, there have been three attacks to the power grid.

The blackout is another blow for Prime Minister Nawaz Sharif, who has been solving a fuel crisis and political opposition. Fixing the electricity system was one of the campaign promises Sharif made, which helped him in a landslide victory.

However, government departments and military bases failing to pay their electricity bills has forced power companies to abandoned needed upgrades, due to lack of funds.

The only sign of progress is agreements with China, signed last year, to build four new power stations.