Police yesterday claimed that an operative of banned militant outfit Jama'atul Mujahideen Bangladesh (JMB) confessed to his involvement in the killing of Rajshahi University teacher Prof AFM Rezaul Karim Siddiquee.

Law enforcers produced the arrestee -- Maskawat Hasan alias Sakib alias Abdullah of Bogra -- before the court of Rajshahi Metropolitan Magistrate Khalid Hossain in the afternoon.

“In his confession, he said he was involved in the murder,” Rajshahi Metropolitan Police Commissioner Shamsuddin told The Daily Star.

“He is an operational commander of Rajshahi region of the militant group,” he said.

Police did not say when they arrested Hasan or from where.

Unknown assailants hacked to death Prof Siddiquee on the morning of April 23 when he was waiting for the university bus in Shalbagan area of Rajshahi city.

His son Riyasat Imtiaz Shourav filed a case with Boalia police station accusing unnamed people for the murder.

Later, police arrested three people, two of them with Shibir affiliations.

Police investigations found three youths, who went to the killing spot by a motorcycle, orchestrated the murder. They left the scene shouting “Allahu Akbar”.

Militant group Islamic State claimed responsibility for the attack, according to US-based SITE Intelligence Group, which monitors global terror activities.

“#ISIS' 'Amaq Agency reported the group's responsibility for killing Rajshahi Univ. prof Rezaul Karim for "calling to atheism" in #Bangladesh,” SITE tweeted hours after the killing.

The government maintains there is no IS presence in the country.