Army Chief Gen Qamar Javed Bajwa has taken notice of and ordered an immediate inquiry into the "Karachi incident", the military's media wing said on Tuesday.

He has directed the Karachi Corps Commander to "immediately inquire into the circumstances to determine the facts and report back as soon as possible", according to the statement issued by the Inter-Services Public Relations (ISPR).

While the ISPR did not specify which incident it was referring to, the statement came minutes after PPP Chairperson Bilawal Bhutto-Zardari called on Gen Bajwa and Director General Inter-Services Intelligence (ISI) Lt Gen Faiz Hameed to investigate the circumstances surrounding the arrest of PML-N leader retired Capt Mohammad Safdar in Karachi a day earlier.

In a tweet from its official account, the PPP said Gen Bajwa also called Bilawal "over the telephone to discuss the Karachi incident this evening".

"The Chairman PPP expressed his appreciation to the COAS for taking prompt notice of the Karachi incident and his assurance of conducting a transparent inquiry on the incident," it added.

Safdar and his wife, PML-N Vice President Maryam Nawaz, were in the city to attend a rally of the opposition's Pakistan Democratic Movement (PDM) when he was arrested from their hotel early on Monday morning. He was subsequently released on bail.

Addressing a press conference in Karachi, Bilawal said all top officers of Sindh Police were wondering "who were the people who surrounded" the Sindh police chief's house in the early hours of Monday and took him to an unspecified location before Safdar was arrested.

He also demanded to know the identities of "the two people who went inside the IG's house" and where they allegedly took the police chief at around 4am.

"I demand of DG ISI Faiz Hameed and Chief of Army Staff Gen Bajwa to investigate your institution [and] how it is operating in this province," the PPP leader said, adding that the provincial government will carry out its own inquiry.

He said the advice to carry out Safdar's arrest in that manner was "wrong" and could damage the armed forces' "institutional integrity".

Following Safdar's arrest, a purported voice message by PML-N leader and former Sindh governor Muhammad Zubair was shared by a journalist in which Zubair alleged that the inspector general of police was kidnapped and forced to register the first information report against Maryam, her husband Safdar and 200 others for violating the sanctity of Quaid-i-Azam Mohammad Ali Jinnah's mausoleum.

In the audio clip circulating on Twitter, Zubair purportedly said that Chief Minister Murad Ali Shah confirmed to him that police was pressured into making the arrest. "When they (police) refused to do that, Rangers kidnapped [the IGP]," Zubair said.

Maryam had also alleged that the Sindh police chief was forcibly "taken to the sector commander's office and asked to sign on the arrest orders". She claimed that when the IGP showed reluctance, he was told that the arrest would be carried out by the Rangers. "After his signatures were forcibly taken on the arrest orders, he was told police would carry out the arrest."

The allegation was denied by Maritime Affairs Minister Ali Zaidi as "nonsense narrative".

I am ashamed: Bilawal

Terming the manner in which Safdar was arrested as "shameful", Bilawal said he could not condemn it enough.

"I am ashamed [and] unable to show my face over what has taken place in my province," he added.

He said there was a furore over the political slogans raised by Safdar at the Quaid's mausoleum, but asked why no action was taken when PTI workers "did similar sloganeering" during Imran Khan's visit to the tomb and when "banned outfits" raised their own slogans there.

"Harassing them (Maryam and Safdar) early in the morning and arresting Safdar is an insult to the people of Sindh who had invited Maryam sahiba and the N-league delegation to attend the PDM jalsa," the PPP leader said.

He said the numbers in which the people of Sindh had attended the rally was "an open referendum against Imran Khan and his facilitators".

Vowing that the Sindh government will fully pursue the investigation into the episode involving Safdar's arrest, Bilawal said a number of top Sindh Police officers were "resigning or going on leave" because the incident had become a "question of their honour".

He said the Sindh government did not want any political interference in the police "but this does not mean we will tolerate interference from somewhere else".

"How does it make sense that the IG is holding a meeting at 4am about some slogans that were raised at the Quaid's mausoleum?" he said, adding that there were many other issues to discuss in meetings.

"The job of the offices of such an important institution in this province should be [regarding] national security [and] to maintain peace in the province.

"If there is no respect left for my police, how will they do their jobs? This is unacceptable," Bilawal stressed.

He said "there should be some red lines which are not to be crossed" and, "I think many red lines were crossed in this incident which should not become a precedent."

Bilawal was asked by a journalist whether it was through a strategy that Chief Minister Shah had not issued the hard-hitting statements that he (Bilawal) did during his press conference earlier in the day. According to the journalist, police officers were "disappointed" that Shah had "not once" taken the IG's name during his presser.

In response, Bilawal said the police officers were going on leave because they were disrespected "not by the chief minister, but from somewhere else". He said the entire PPP and Sindh government stood with the police department.

'Pakistan has changed'

Maryam on Twitter lauded Sindh Police officers for stepping back from their duties over the incident. "I salute the Sindh Police!," she wrote, including a quote by the Quaid-i-Azam advising public servants "not [to] fall victim to any pressure".

She said it was "heartening to see civilians breaking shackles of fear, standing up for supremacy of constitution & reclaiming their long lost rights. The conspiracy & conspirators stand badly exposed."

She also thanked Bilawal for his "support and clear stance", saying "Pakistan has changed."

Meanwhile, PML-N supremo Nawaz Sharif said the events that unfolded in Karachi were "clear proof of our narrative that there is 'a state above the state'".

Without naming anyone, he said: "You made a mockery of the elected provincial government's powers" and "brought a bad name to the Pakistan Army".

'Cruel joke'

Reacting to Bilawal's statements, Minister Ali Zaidi said: "Sindh government and its inept governance are proving to be a cruel joke as IG & Additional IG go on long leave in the aftermath of Capt Safdar’s arrest."

"Who is really in charge of this government which is being run worst than a zoo?" he asked.

Zaidi alleged that even "simple enforcement of the law in Sindh has become laughable due to the politicisation of police by PPP for 12+ years".

"How can they even think of publicly claiming that the IG was kidnapped in the middle of the night! Who are they trying to fool?"