Pakistani supporters of religious party Jamaat-e-Islami offer in absentia funeral prayers for former Bangladeshi politician Ghulam Azam in Islamabad, yesterday. Photo: AFP

Former Bangladeshi politician Ghulam Azam, who died on Thursday just two weeks short of his 92nd birthday, was a convicted war criminal compared by prosecutors to Nazi leader Adolf Hitler.

Azam, the ex-head of the Jamaat-e-Islami party, was serving a 90-year jail term for masterminding widespread atrocities during Bangladesh's 1971 war of independence with Pakistan when he died of a heart attack.

Azam started out as a political science professor and author of over 100 books, experimenting with left-wing politics before joining Jamaat in the 1950s.

He led the party when Bangladesh went to war, in which three million people would die, against Pakistan.With Azam at the helm, Jamaat opposed Bangladesh's secession from Pakistan.

A special court set up by the Bangladesh government concluded in July last year that Azam had orchestrated the establishment of several pro-Pakistani militias which massacred intellectuals at the end of the nine-month conflict.

When India intervened in the war it became clear Pakistan would lose and Azam "masterminded" the killing of dozens of professors, playwrights, doctors and journalists, the court said.

Many of whose bodies were found a few days after the war ended in a marsh outside the capital, their hands tied behind their backs and blindfolded as if they had been executed.

"The aim was to cripple the country intellectually. Without his consent it could not have happened," state prosecutor Sultan Mahmud said on the day of Azam's conviction.

"His role in the 1971 war was like Hitler's in the Second World War," Mahmud added.

After the war, Azam fled to Pakistan where he allegedly formed the East Pakistan Restoration Committee, portraying the liberation war as a conspiracy by India. He left Pakistan for London in 1973 where he continued to campaign against recognising Bangladesh's independence.

After independence, Bangladesh cancelled Azam's citizenship and banned Jamaat and other faith-based parties. Thousands were arrested for collaborating with Pakistan.

But a deadly turn in Bangladesh's volatile politics brought Azam back to Dhaka on a Pakistani passport in 1978, three years after the nation's founding leader Sheikh Mujib was assassinated. A junta had taken over and was allowing Islamic parties to operate openly again.

Although his party has never won more than five percent of votes, Azam has played the role of kingmaker repeatedly since democracy was restored in 1990. He shifted alliances, helping the nation's two main rival parties to return to power in turn and in the process reviving the fortunes of the once universally despised Jamaat party.

His political rehabilitation was complete in 1993 when the Supreme Court returned his citizenship.

In January 2012, Azam was arrested. Eighteen months later his fate was sealed.