Family members of Sherkhan Farnoon, the founder and former head of the old Kabul Bank, who reportedly died of heart disease at Bagram Prison on Friday, said Farnoodís burial ceremony will be delayed until an autopsy has been carried out by the forensic medicine department.
The family said his death was unexpected and suspicious. This comes after the Ministry of Defense on Friday said Farnood, 57, had died of "heart disease".
The former banking executive was serving a 15-year sentence at Bagram Prison after being found guilty of being part of the $900 million Kabul Bank embezzlement scandal in 2014.
Farnoodís family said they want justice and a thorough investigation into his death.
"I talked with my brother one day before (his death). He was fine. We have no idea about it, government knows how he died," said Sherin Khan, elder brother of Farnood.
Farnoodís nephew said that the Kabul Bank founder died soon after eating breakfast.
"We have heard this from Bagram Prison officials but we cannot confirm it because the facts are not known so far," said Shah Khan Shirzad, Farnoodís nephew.
The Ministry of Public Health said the reason behind Farnoodís death will be made clear within a week.
"(Forensic) samples have been taken. They will be assessed by standard machines and results will be out within a week," said Wahid Majroh, spokesman for Ministry of Public Health.
An official from the Afghanistan Chamber of Commerce and Industries (ACCI) said conditions Farnood had been subjected to had been questionable.
"These individuals should have been kept in a civilian prison not in a military prison where conditions are tough," said Atiqullah Nusrat, CEO of the ACCI.
Kabul Bank, once the countryís largest financial institution, collapsed in 2010 in one of the largest banking scandals in the countryís history.
The former chairman of Kabul Bank, Sherkhan Farnood, and CEO Khalilullah Frozi were sacked from their positions and arrested over the embezzlement of more than $900 million in cash and assets.
Frozi and Farnood were each sentenced to 15 years in jail after they were found guilty of being party to the collapse of Kabul Bank, which is now run by government.
In November 2015, government launched the íSmart City Townshipí Project in which Khalilullah Frozi was a part.
Government officials said the aim of the program was to help the debtors of Kabul Bank repay their debt instead of being imprisoned.
The move however sparked an outcry.
In February 2016, President Ashraf Ghani cancelled the contract of the Smart City Township.
Sherkhan Farnood was the chairman of Kabul Bank until late 2010, which was Afghanistanís largest private financial institution with over one million customers at the time.
Farnood held a 28.16 percent share in the old Kabul Bank. By November 2010 both Farnood and Frozi had been suspended.
As of early 2011, both were effectively under house arrest and could not leave the country.