Dhaka: Bangladesh war crimes investigators moved on Tuesday to outlaw the country's largest Islamic party, accusing it of genocide and other atrocities during the 1971 bloody struggle for independence.

Government investigators handed a report detailing war crimes allegations against Jamaat-e-Islami to prosecutors, in the latest move against the party which has banned from contesting January elections.

"We want total dissolution of the party," the government's chief war crimes investigator Abdul Hannan Khan told reporters.

"Jamaat and its wings took the decision to act as auxillary forces of the Pakistani army in committing atrocities in the 1971 war. So the party cannot avoid its superior responsibilities," Hannan said.

Hannan said prosecutors from the country's controversial war crimes tribunal would now proceed with charges against the party which would lead to a trial in the same tribunal.

"The whole nation has been waiting for this trial. It is the first time after the Nuremberg and Tokyo trials that a party is to be prosecuted for war crimes," Hannan said, comparing Jamaat to the Nazi party.

The tribunal, set up by the secular government in 2010, has already convicted more than a dozen of Jamaat's leaders over crimes allegedly committed during Bangladesh's war against Pakistan for independence.

A senior Jamaat leader was executed in December after his conviction, sparking a fresh wave of deadly protests by Islamist supporters.

Protesters have repeatedly clashed with police over the tribunal, which Islamists claim is aimed at eradicating its leaders, leaving more than 200 people dead since last January when the verdicts were first handed down.

Jamaat, a leading opposition party, was banned from contesting general elections held in January this year which were boycotted by other opposition parties and marred by bloodshed.

The country's top court ruled last August that Jamaat be banned because its charter followed Islamic law that conflicted with the nation's official secular constitution, although the party was allowed to hold rallies.

There was no immediate comment from Jamaat but the party has earlier accused the country's government of organising show trials in an effort to destroy it.

Prime Minister Sheikh Hasina's government says three million people died in the war, many at the hands of pro-Pakistan militias led by Jamaat leaders who opposed secession from Pakistan on religious grounds.

Independent researchers put the death toll between 300,000 and 500,000 people.