DHAKA: Bangladesh hanged a wealthy tycoon and top financial backer of its largest religious party on Saturday for alleged war crimes, the country's law and justice minister said.

Mir Quasem Ali, a key leader of the Jamaat-e-Islami party, was hanged at a high security prison outside the capital Dhaka after he was convicted of offences committed during the 1971 war, Anisul Huq told AFP.

“The execution took pace at 10:35 pm (local time),” he said.

Ali was convicted by a controversial war crimes tribunal for offences committed during the 1971 independence conflict.

After the Supreme Court rejected his final appeal against the penalty on Tuesday, Ali declined to seek a presidential pardon, which would require an admission of guilt, paving the way for his execution.

Two other police officials speaking on condition of anonymity told AFP that the execution would occur between 10:00 pm Bangladesh time and midnight.

Ali is said to be a key commander of the Al-Badr militia in the southern port city of Chittagong during the 1971 war, and later became a shipping and real estate tycoon.

Russel Sheikh, a senior Gazipur police official, told AFP that officials have taken “highest security measures” ahead of the planned execution for fear of violence by his supporters.

“More than 1,000 police have been deployed in the district,” Sheikh told AFP.

Past convictions and executions of high-profile JI leaders have triggered violence in Bangladesh, which is polarised along political lines.

“All along he said he was innocent. He said he is being killed unjustifiably,” said Tahera Tasnim, one of Ali's daughters after 23 members of his family went to meet him in the jail.

“He said this repressive government is killing them (religious leaders),” Tasnim told AFP.

The Supreme Court's decision to reject Ali's appeal was a major blow for the JI, which the 63-year-old tycoon had helped to revive in recent decades.

Five opposition leaders including four leaders of JI have been executed for war crimes since 2013.

Ali is the last prominent JI leader to face execution.

The war crimes tribunal set up by the government has divided the country, with supporters of JI and the main opposition Bangladesh Nationalist Party (BNP) branding it a sham aimed at eliminating their leaders.

Ali was convicted in November 2014 of a series of crimes during Bangladesh's war of separation from Pakistan, including the abduction and murder of a young independence fighter.

His son Mir Ahmed Bin Quasem, who was part of his legal defence team, was allegedly abducted by security forces earlier in August, which critics say was an attempt to sow fear and prevent protests against the imminent execution.

The religious party, which is banned from contesting elections has labelled the charges against Ali “false” and accusing the government of exacting “political vengeance”.