Pakistan Tehreek-e-Insaf (PTI) Vice Chairman Shah Mahmood Qureshi was arrested on Saturday from his residence in Islamabad, Aaj News reported.

Qureshi was taken to the Federal Investigation Agency (FIA) headquarters in the capital after his arrest.

According to sources, Qureshi was detained in connection with a cipher case.

The PTI Vice Chairman has been detained twice in the past three months, first in connection with a case involving May 9 violence and now in connection with the cipher case.

The development comes after the FIA registered a case against PTI Chairman and former prime minister Imran Khan for allegedly losing a copy of a diplomatic cipher.

Sources said that the first information report (FIR) against Khan was registered by the Counter-Terrorism Wing of the FIA.

A joint inquiry team has already started the investigation following the direction of the previous government regarding charges of prejudicing the national security and interest of the state by directly revealing, without proper authorisation, the classified information by the former prime minister Imran Khan, his political associates, and the secretary to the former prime minister through cipher telegram, its subsequent misuse, and unauthorised retention. Khan appeared on July 25 before the investigation team and recorded his statement.

They said that the inquiry team also conducted an investigation of Khan at Attock jail a few days ago.

On March 27, 2022, Imran Khan, then prime minister, claimed there was a foreign conspiracy afoot to overthrow his government.

Using his D-Chowk address, Imran did not mention the US or the countries involved. “I seldom write my speeches but I wrote this speech today so that I don’t get emotional and say anything which can affect our foreign policy,” he had said.

While taking out a piece of paper from the pocket of his black waistcoat, claiming it evidence, Imran had also said: “We got to know about it [foreign conspiracy] a few months back…if anyone has any doubt, I can show the letter to him but it would be off the record,” the PM said.

“We know from where attempts are being made to pressure us…we’ve been threatened in writing but we will not compromise on national interest no matter what,” he declared.

A few days later, with the no-confidence motion gathering momentum, Imran -- during another live address -- mentioned the US by name before retracting it. After his ouster as prime minister, Imran doubled down on the narrative before saying this year that the “regime change conspiracy” against his government was hatched in the country, not the United States.

The Intercept's report

Earlier this month, The Intercept, a US-based news organisation, published a report on the basis of the 'cipher' document.

"The document, labeled 'Secret,' includes an account of the meeting between State Department officials, including Assistant Secretary of State for the Bureau of South and Central Asian Affairs Donald Lu, and Asad Majeed Khan, who at the time was Pakistan’s ambassador to the U.S," The Intercept wrote in its description.

As per the purported contents of the cable, the US objected to Imran's foreign policy regarding the Ukraine war, with the report quoting Lu as saying, “people here and in Europe are quite concerned about why Pakistan is taking such an aggressively neutral position (on Ukraine), if such a position is even possible. It does not seem such a neutral stand to us.”

Lu further said that he had held internal discussions with the US National Security Council and that “it seems quite clear that this is the Prime Minister’s policy.”

“I think if the no-confidence vote against the Prime Minister succeeds, all will be forgiven in Washington because the Russia visit is being looked at as a decision by the Prime Minister,” Lu said, according to the document.

“Otherwise, I think it will be tough going ahead.”

Lu also warned that if the situation was not resolved, Pakistan would be marginalised by its Western allies.

“I cannot tell how this will be seen by Europe but I suspect their reaction will be similar,” Lu said.

Responding to The Intercept's report, the outgoing Prime Minister Shehbaz Sharif said that if the alleged contents of a diplomatic cipher, cited by ex-premier Imran Khan as proof of an attempt to remove his government, were true, that would be a “massive crime”.

Earlier, former interior minister and Pakistan Muslim League-Nawaz (PML-N) leader Rana Sanaullah called for an investigation into the authenticity of the source document that formed the basis of The Intercept's report on the 'cipher', which Pakistan Tehreek-e-Insaf (PTI) Chairman Imran Khan claimed was proof of a US conspiracy to remove his government last year.

"Though there is nothing new in this story, the investigation needs to (be) held to establish the authenticity of the information or source document," he tweeted on Thursday. "Potentially, it is a very sinister, treacherous, and seditious act."