Former premier Nawaz Sharif and his daughter Maryam Nawaz were arrested by National Accountability Bureau (NAB) officials upon their arrival in Lahore on Friday night, and subsequently whisked away to Islamabad on a chartered flight.
The two were separated and taken from the Islamabad International Airport in two convoys to the Central Jail in Adiala, Rawalpindi, for a medical examination.
As per official procedure, the examination was carried out in the presence of the Islamabad magistrate and senior police officials.
The penitentiary's medical board compiled reports on Nawaz and Maryam's medical history and declared them fit for incarceration in the facility.
Nawaz spent the night in one of the rooms of the jail's high security zone, whereas Maryam was transferred to the women's barracks.
Meanwhile, a NAB prosecution team had approached the accountability courts seeking an exemption for Nawaz and Maryam's appearance before the court. NAB Additional Deputy Prosecutor General Sardar Muzaffar Abbasi told the court that the convicts cannot be produced before the court due to a high-security risk.
The accountability court conceded the request and appointed Magistrate Wasim Ahmed to execute the warrants of imprisonment at Adiala. By this exercise, the authorities eliminated any chance of producing Nawaz and Maryam before the court the same night or next morning.
Media representatives who had gathered to cover the production of Nawaz and Maryam before the court were not allowed to enter the premises of the court complex.
There had been a lack of clarity till late Friday night over where the two would ultimately be incarcerated, at least for the short term.
The Islamabad chief commissioner had initially issued a notification declaring the Sihala Police Training College Rest House in the capital city "as sub-jail for keeping the convicted prisoner Mian Muhammad Nawaz Sharif, ex-prime minister, and Mariam Nawaz, who have been arrested by NAB authorities, with immediate effect and till further orders."
However, a second notification had followed, stating that Sihala would serve as a sub-jail only for Maryam and that the preceding notification would be considered void ab initio.
Conflicting reports had continued to make the rounds, with some stating that both Nawaz and Maryam would be incarcerated at Adiala, while others said Maryam would be separated and shifted to the Sihala rest house. They were eventually both confined to Adiala for the night.
Nawaz and Maryam had taken off from Abu Dhabi for Lahore shortly after 6pm PST on the last leg of their journey home from London.
Their flight, Etihad Airways flight EY243, was earlier scheduled to land at 6:15pm PST at Lahore's Allama Iqbal International Airport, but suffered a nearly three-hour delay.
An airport official, when approached by our correspondent, had stated the reason for the hold-up in Abu Dhabi as a delay in an Etihad flight arriving from Bangkok, which was supposed to fly EY243's passengers to Lahore.
The flight eventually took off at nearly 6pm PST and landed in Lahore at 8.45pm.
According to media reports, dozens of security officials entered the plane after it landed and asked other passengers to leave. The duo's passports were seized by a three-member Federal Investigation Agency (FIA) team. Their immigration formalities were completed on board the plane.
The two were taken into custody at around 9:25pm and put on a chartered plane to Islamabad.
Nawaz and Maryam had been convicted by an accountability court in the Avenfield corruption reference last Friday and handed jail sentences of 10 years and seven years, respectively. The former was found guilty of owning assets beyond known income, while his daughter was convicted for aiding and abetting her father in covering up a "conspiracy".
After the verdict was announced, Nawaz and Maryam had said they would return to Pakistan and appeal against the decision.
The National Accountability Bureau (NAB) and Punjab government had made arrangements to take the father-daughter duo into custody upon arrival and shift them to Adiala Jail, where they are supposed to serve their jail term.
In Lahore, authorities had braced to maintain law and order as thousands of PML-N workers and supporters had gathered at various points in the city to welcome the ousted premier and his daughter.
Large parts of the city were locked down as the state seemed determined to prevent supporters from reaching the airport.
PML-N President Shahbaz Sharif, whose caravan had gathered at Lohari Gate, had led the main welcoming rally to the airport to accord his brother and PML-N supremo Nawaz a warm welcome.
When Nawaz and Maryam were flown out, he was en route to the airport. PML-N workers who were part of the rally were chanting slogans of "Rok sako tau rok lo (stop us if you can)" and "Vote ko izzat do (respect the vote)".
According to media reports, no PML-N supporters were allowed onto airport premises.