The demonstrations were sparked by demands for Khan’s release from jail and the resignation of the federal government over what they call rigged general elections this year.

As the situation worsened in Pakistan's capital Islamabad amid fierce protests demanding the release of former prime minister Imran Khan, the government asked the army to intervene.

Supporters of the ex-prime minister marched toward Islamabad, the capital. Clashes with the police left at least one officer dead, the authorities said.