Incarcerated former prime minister Nawaz Sharif, who is serving a 10-year jail term after being convicted for owning assets beyond income in the Avenfield reference, was shifted from Adiala Jail to Islamabad's Pakistan Institute of Medical Sciences (Pims) after developing serious cardiac complications, DawnNewsTV reported on Sunday.

TV footage showed a convoy of vehicles, including police vans, an armoured personnel carrier and at least two ambulances, on the road after leaving the jail in the evening.

As the convoy carrying Sharif reached Pims, his supporters who had gathered at the hospital chanted slogans in his favour.

Pims spokesman Wasim Khwaja said Sharif was in the hospital's Cardiac Centre and his condition was stable. He said besides hospital security, extra police and paramilitary troops were deployed in and around the premises.

The three-time former prime minister was shifted to the presidential suite of the Cardiac Centre, hospital sources told DawnNewsTV.

A check-up at the hospital revealed that Sharif's sugar level is high and he is suffering from stress, the sources said, quoting doctors.

Caretaker Punjab home minister Shaukat Javed said on state-run PTV that doctors had advised his transfer to hospital after an electrocardiogram had shown “variations”.

“How many days he stays in hospital depends on doctors,” Javed said.

Earlier today, Dr Naeem Malik, head of the Pims cardiology department, suggested that authorities shift Sharif to the hospital as his blood tests showed clotting which, according to the doctor, was an alarming sign considering his medical history. The PML-N supremo lives with diabetes and has also undergone bypass surgery. He currently takes medication for his heart condition, cholesterol and diabetes.

Sharif's personal physician also reached Adiala Jail on Sunday evening to examine him. Later, a meeting between Sharif and his daughter Maryam and son-in-law retired Capt Mohammad Safdar took place to discuss his health condition.

Last week, the former PM was suffering from dehydration and his blood urea content was 50 per cent higher than it should have been. A medical team also recommended that he be shifted to the hospital as his heart beat was not normal and the presence of urea in the blood may affect his kidney.

However, Sharif refused to be moved to a hospital and insisted that medical treatment be provided to him in prison.

According to jail sources, the doctors today advised moving Sharif to the critical care unit as he has been suffering from acute pain in both his arms, likely due to lack of adequate blood circulation.

After the doctor's examination, jail authorities contacted the caretaker government to apprise it of the development. The provincial government had no objections towards moving Sharif to the hospital, but placed responsibility for his security on the Islamabad police, since he had been convicted by an accountability court and his security fell into the jurisdiction of the capital force.

Meanwhile, security had been beefed up in and around the jail. Security personnel had been deployed around its premises and the media was advised to steer clear of the premises.