The Pakistan Tehreek-e-Insaf (PTI) supremo, who was ousted in a no-confidence motion last year, was whisked away by the paramilitary Rangers from Islamabad High Court and bundled into a prison van in a corruption case. His arrest sparked massive protests across the country by PTI supporters and his followers.

The 70-year-old will be presented before the accountability court on Wednesday, a NAB source was quoted as saying by Karachi-based English daily Dawn. “We will do our best to keep him under custody for at least four to five days,” the unidentified source was quoted as saying.

Under new amendments to the National Accountability Ordinance, 1999, the duration of physical remand has been cut from 90 days to 14 days, granted by any court. “We will seek the maximum physical remand of 14 days from the court,” he told the newspaper, adding that the court was expected to grant at least four to five days remand.

The arrest comes a day after Pakistan’s powerful army accused Khan of levelling baseless allegations against a senior officer of the spy agency ISI.

Speaking on the condition of the PTI chief, the official told Dawn that Khan was detained in NAB’s Rawalpindi/Islamabad regional headquarters “in a comfortable atmosphere”. He will not be “treated harshly”, rather he will only be questioned regarding his alleged involvement in the case and seeking monetary benefits.

Violent protests erupt across Pakistan

As the news of the former Pakistan PM’s arrest spread, protesters took to the streets across cities including Lahore, Peshawar, Karachi, Gilgit and Karak. Agitators burned police vehicles and damaged public property. Video footage shows that some PTI workers suffered bullet injuries in Lahore and Faisalabad during their clashes with the security agencies.

For the first time, Khan's supporters smashed through the main gate of the Army's sprawling headquarters in Rawalpindi, where troops exercised restraint. The protesters chanted slogans against the establishment.

They also set on fire a toll plaza on the Swat Motorway, according to footage shared on social media platforms.

A senior leader of the Pakistan Tehreek-eInsaf has claimed at least four of its party workers were killed and over a dozen injured in different parts of the country in violent clashes between the security forces and Khan’s supporters.

"At least four PTI workers were killed so far in different parts of the country on the firing of the law enforcement agencies. One each has been killed in Lahore, Faisalabad, Quetta, and Swat," said PTI leader Shireen Mazari on Tuesday.

What is the case in which Imran Khan was arrested?

In an official statement, the NAB said that Khan has been arrested in the case related to Al-Qadir Trust, owned by the PTI chairman and his wife Bushra Bibi, which is about the setting up of Al-Qadir University for Sufism in the 2019 Sohawa area of Jhelum district of Punjab.

Khan's arrest warrant, issued on May 1, said that he was accused of corruption and corrupt practice.

The anti-graft watchdog has justified the PTI chief's arrest saying it “has been made after fulfilling the lawful procedures of inquiry and investigation conducted by NAB”.

“NAB arrested former prime minister Imran Khan in the Al-Qadir Trust case. The case relates to illegal acquisition of land and construction for Al-Qadir University involving unlawful benefit given in recovery of prime proceeds (190 million pounds) through National Crime Agency, UK,” the statement said.

It said during the process of inquiry/investigation, several notices were issued to Khan and his wife as they were the trustees of Al-Qadir Trust.

“However, none of the call-up notices was responded to by the former prime minister or his wife.”

Meanwhile, the NAB is also out to arrest other alleged characters in the Al-Qadir University and Trust case and has completed the process to issue a red warrant through Interpol to arrest Khan’s former adviser on accountability, Shehzad Akbar, who they termed as “the key person” in the case.

“He (Akbar) and the former prime minister misled the federal cabinet by concealing the documents related to the settlement agreement. Money was received under the settlement agreement and was supposed to be deposited in the national exchequer,” it added.

The NAB statement said the process of issuing of Red notice against former adviser Akbar, who is absconding, has already been initiated.

(With PTI inputs)