An Islamic State group affiliate in Bangladesh said on Friday it was behind an attack on a Shiite mosque in the country's north that killed one man and wounded three others.

A statement posted on IS-affiliated Twitter accounts from Islamic State-Bangladesh said that the mosque was hit by a barrage of shots fired from machine guns.

At least five assailants fired on worshippers during evening prayers on Thursday at the mosque in Haripur village in the Bogra district. A mosque official in his 70s who had been leading the prayers was killed.

Police detained two suspects on Friday for questioning, said local police official Arifur Rahman.

He said the men were picked up from the area of the attack. Details of their identities were not immediately clear.

The statement from the IS offshoot said, "the soldiers of the caliphate targeted a place of worship for the apostates" built with funds from Iran. It vowed more such attacks.

Thursday's attack follows a wave of deadly assaults this year on foreigners, secular writers and the Shiite community in the Sunni-majority nation of 160 million.

The attacks have alarmed the international community and raised concerns that religious extremism is growing in the traditionally moderate South Asian nation.

Bangladesh's government has repeatedly denied the presence of the IS group in the impoverished nation.

Police have arrested six members of the banned local group Jumatul Mujahedeen Bangladesh in connection with the Oct 24 bombing of an annual rally of thousands of Shiite Muslims in Dhaka, according to senior Detective Branch official Munirul Islam. The bombs, lobbed into the crowd as people were gathering for an early morning procession through the capital, killed a teenage boy and wounded more than 100 people.

Authorities had quickly dismissed a claim of responsibility by the Islamic State group in that attack too, saying it had no presence in the country, and that the culprits were likely from Jumatul Mujahedeen Bangladesh.

On Thursday, security officials killed the alleged mastermind of the Oct. 24 attack, Al Bani, during a gunfight.

(China Daily 11/28/2015 page8)