DHAKA: Police have detained two members of Bangladesh's biggest religion-based party on suspicion they were involved in Islamic State propaganda, including one who called himself "Jihadi John", a police commissioner said on Wednesday.

The two members of the Jamaat-e-Islami Party who were paraded before reporters are being investigated for links with militant Islamic State (IS) group which has claimed responsibility for a series of attacks in Bangladesh including the killing of two foreigners.

Nahid Hasan was picked up from Dhaka overnight on suspicion that he was spreading hate and violence on behalf of IS using the pseudonym Jihadi John on a Facebook page, police joint commissioner Monirul Islam said.

"We are verifying whether he actually had contacts with the radical group," Islam said.

The government has consistently denied that IS has a presence in the country and instead blamed religious groups such as the Jamaat for instigating violence in the Muslim but secular nation of 160 million people.

Police said the second man arrested in the overnight raid was believed be behind text messages threatening writers and university teachers who have been targeted by unknown assailants this year.

Tensions have been rising in Bangladesh over the trials of Islamists for war crimes during its struggle for independence in 1971 and some leaders of the Jamaat as well as its ally, the Bangladesh Nationalist Party, have been executed.

Critics say the government is using the war trials to settle political scores.

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