Violent clashes have broken out in Pakistan between security forces and supporters of former prime minister Imran Khan after he was arrested on Tuesday.
Protests are erupting nationwide, and at least one person has been killed in the city of Quetta.
The United States and UK have called for adherence to the “rule of law”.
Mr Khan was arrested by security forces at the High Court in the capital, Islamabad.
Dramatic footage showed dozens of officers arriving and detaining the 70-year-old, who was bundled into a vehicle and driven away.
He was appearing in court on charges of corruption, which he says are politically motivated.
Mobile data services in the country were suspended on the instructions of the interior ministry on Friday as protests grew, many of them taking place in front of army compounds.
Pakistan's army plays a prominent role in politics, sometimes seizing power in military coups, and, on other occasions, pulling levers behind the scenes.
Many analysts believe Mr Khan's election win in 2018 happened with the help of the military. Now in opposition, he is one of its most vocal critics, and analysts say the army's popularity has fallen.
Footage from Lahore posted on Twitter appeared to show a crowd breaking into the military corps commander's house destroying furniture and belongings inside.
Speaking from Washington, the US Secretary of State Antony Blinken said he wanted to make sure that “whatever happens in Pakistan is consistent with the rule of law, with the constitution”.
UK Foreign Secretary James Cleverly, speaking alongside Mr Blinken, noted that Britain enjoyed “a longstanding and close relationship” with Commonwealth member Pakistan, and wanted to “see the rule of law adhered to”.
On Tuesday evening, supporters of Imran Khan gathered outside the Pakistan High Commission in London to protest against his arrest.