Pakistani authorities arrested a senior leader of former Prime Minister Imran Khan's party on Thursday as the government deployed the army to help end deadly unrest sparked by Khan's arrest three days ago.

Shah Mahmood Qureshi, who served as foreign minister in Imran Khan's cabinet during his four year premiership, was arrested overnight, a statement on his Twitter profile said.

Two other senior leader of Khan's Pakistan Tehreek-e-Insaf (PTI) party, Asad Umar and Fawad Chaudhry, were also arrested on Wednesday.

The violence sparked by Khan's arrest on Tuesday by the country's anti-graft agency has aggravated instability in the country of 220 million people as it grapples with a severe economic crisis and a delay to an International Monetary Fund bailout since November.

Protesters have stormed military buildings and ransacked the residence of a top army general in the eastern city of Lahore.

Other state buildings and assets have been attacked and set ablaze by protesters. At least five people have died in the violence.

The federal government Wednesday approved requests from two of Pakistan's four provinces - Punjab and Khyber Pakhtunkhwa, both Khan strongholds - and the federal capital Islamabad to deploy troops to restore order.

The Islamabad police said on early on Thursday that troops have reached the capital city.

Police have arrested more than 1,300 protesters in Khan's home province of Punjab for violence.

Separately, Khan was indicted by a Pakistani court in an unrelated case on Wednesday for unlawfully selling state gifts during his premiership between 2018 and 2022.

The corruption cases against Khan are two of more than 100 cases registered against him since his ouster in April 2022 in a parliamentary no confidence vote. He has not slowed his campaign against the ouster even after being wounded in a November attack.