Three days into the killing of secular online activist Nazim Uddin Samad, investigators have yet to find out clue to the gruesome murder.

When asked about progress of the investigation, investigation officer Samir Chandra Sutradhar of Shutrapur Police Station, told The Daily Star that there is no new information worth sharing with the media.

He confirmed that Nazim did not write any blog but used to post his write-ups on his Facebook page.

"We are looking into several aspects: trying to find whether Nazim had enmity with anyone, scrutinising his Facebook posts and checking whether he had any land or family disputes," he said.

Nazim, a law student at Jagannath University, was hacked and shot to death by unidentified assailants on the capital's Hrishikesh Das Lane on Wednesday night.

Militant group Ansar al-Islam claimed responsibility for the murder of Nazim, according to US-based SITE Intelligence Group, two days in to the killing.

In a statement posted online, SITE said, "Ansar al-Islam, the Bangladesh division of al-Qaeda in the Indian Subcontinent (AQIS), claimed credit for the murder of blogger Nazim Uddin Samad in the capital, Dhaka."

The Daily Star could not independently verify the claim.