The senior cleric died of a heart attack in the southern holy city of Najaf, according to Nujaba TV.
He “underwent surgery three days ago in a hospital in Najaf and succumbed today to a heart attack”, a source within his office said Friday.
Ayatollah al-Hakim was one of the four Shia sources of emulation in Najaf.
He has written more than 40 books on Islamic Fiqh (jurisprudence). He also trained many scholars in Islamic sciences.
Born to a family of clerics in Najaf in 1354 Hijri (1936), he was a grandson to late Grand Ayatollah Muhsen al-Hakim. His father was Mohammad Ali al-Hakim, one of the most respected clerics in Najaf.
He was considered as the top candidate to succeed the Arab country’s most prominent Shia cleric, Grand Ayatollah Ali al-Sistani, who is in his early nineties.
The source added that a funeral ceremony was arranged to be held on Saturday in Najaf, home to the shrine of Imam Ali, the first Imam in Shia Islam, where he will be buried. A similar ceremony will also be held in the holy city of Karbala.
Iraq’s former dictator Saddam Hossein detained al-Hakim in 1983 and kept him behind bars until 1991. The influential cleric authored dozens of books and monographs, mostly on Shia jurisprudence.
In a statement, Iraqi President Barham Salih paid homage to the “prominent figure” in Shia Islam.
Secretary-General of the Iraqi Parliament Sirwan Abdulla, Iraq's National Security Adviser Qasim al-Araji, and a number of other top Iraqi officials expressed their condolences to al-Hakim’s family, the Iraqi nation, and all Shia Muslims across the world.