The revelations about the money were made in the book "Khalid Khawaja: Shaheed-e-Aman", about the life of an ISI agent.
The book claims Sharif took $15 million to promote jihad in Kashmir and Afghanistan.
More trouble for Nawaz Sharif
What are the allegations?
The allegations date back to the 1980s an 1990s.
Reportedly, several opposition parties also took money from the army and ISI to overthrow Benazir Bhutto and form an opposition to the Pakistan People's Party.
PTI called it "a shady chapter in the country's political history."
Will file 2 cases: Imran Khan
PTI leader Imran Khan said his party would file 2 cases in the SC against Sharif for his attempts "to destabilise and conspire against democracy in Pakistan". One is over the Osama allegation and the other is related to taking money from the army.
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Panama papers leak haunts Sharif
The paper published documents revealing illicit financial gains made by three of Sharif's four children.
He now faces a Supreme Court probe into his family's connections with illegal financial institutions and money launderers.
Sharif, army don't see eye to eye
The Pakistan army has long been considered a state within a state.
In January 2017, the spat between Sharif and the army came to the fore, when a newspaper reported details of a high-level security meet where Sharif allegedly threatened the army to withhold use of terrorism in Kashmir.
Following this, the army is part of the Panama Papers probe panel.
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