Image copyright AFP Image caption Azam was convicted for his role in setting up militias that carried out atrocities during the 1971 war

The controversial former leader of Bangladesh's largest Islamist party, Ghulam Azam, has died at the age of 91.

The former head of Jamaat-e-Islami died from a heart attack on Thursday, a hospital spokesman in Dhaka said.

Last year Azam was sentenced to 90 years in jail after being found guilty of charges relating to Bangladesh's 1971 war of independence with Pakistan.

There were violent clashes between supporters of Jamaat-e-Islami and police after the verdict in July 2013.

"He died of cardiac arrest at 10.10pm today," Abdul Majid Bhuiyan, director of the Bangabandhu Sheikh Mujib Medical University told reporters.

Earlier on Thursday, Azam's son Abdullahel Azmi told AFP news agency that his father's condition had deteriorated, prompting the authorities to put him on life support.

Last year, a court in Dhaka found Azam guilty on five charges including conspiracy, incitement, planning, abetting and failing to prevent murder.

He faced more than 60 counts of crimes against humanity for his role in setting up militia groups that carried out atrocities during the 1971 war.

He had denied the charges, which his supporters argued were politically motivated.

The prosecution had sought the death penalty but the three-judge panel ruled that while he deserved capital punishment, he was given a prison term because of his age.