Pakistan's former Prime Minister Nawaz Sharif, who is serving a 10-year prison sentence, has been hospitalised after suffering heart problems.
Authorities on Sunday moved Sharif from Adiala prison in Rawalpindi to the Pakistan Institute of Medical Science (PIMS) in the capital, Islamabad, on the recommendation of doctors.
Shaukat Javed, a minister for Punjab province where the prison is located, told state media that doctors had examined Sharif, 68, after he complained of chest pains and that an electrocardiogram (ECG) confirmed there were irregularities.
"How many days he stays in hospital depends on doctors," Javed said in comments broadcast by the state-run PTV channel.
Sharif's Pakistan Muslim League-Nawaz (PML-N) party said on Twitter that the former prime minister had agreed to be treated at the hospital after consulting with his personal doctor.
Wasim Khwaja, a spokesman for PIMS, said Sharif was being treated in the hospital's cardiac centre and that his condition was stable.
Extra police and paramilitary troops were deployed to assist hospital security, according to Khwaja.
On July 24, a medical board met to assess Sharif's health and said he was in need of constant medical care, according to Pakistani media.
He is diabetic and has a history of heart problems, undergoing bypass surgery in 2016.
Sharif and his daughter Maryam Nawaz were convicted of corruption on June 6 in a case relating to the ownership of four luxury apartments in London, Britain's capital.
They have been held at the high-security prison since July 13. A court will hear their appeals on July 31.
The PML-N suffered a heavy defeat in Wednesday's general elections, winning only 64 of the 137 seats needed for a parliamentary majority.
The party of Imran Khan, a former cricket player and longtime critic of Sharif, finished first but will need to form a coalition to govern.
Shehbaz Sharif, the PML-N chief and Nawaz's brother, criticised the results as "sheer rigging".
"The way the people's mandate has blatantly been insulted, it is intolerable," he told a news conference on Wednesday.
For his part, Khan has offered to investigate the claims, saying he wants to unite the country under his leadership.
He released a statement on Sunday wishing Sharif a speedy recovery.