Rajshahi University professor AFM Rezaul Karim Siddiquee, 58, was attacked by motorbike-borne assailants within 50 metres of his residence in Rajshahi city as the militants slit his throat using sharp weapons and left him to die, police said.
"The miscreants attacked him from behind with machetes as he walked to the university campus from his home around 7.30 AM," local police station in-charge Shahdat Hossain told PTI over phone.
US-based private SITE Intelligence Group said the Islamic State has claimed the killing.
"ISIS' Amaq Agency reported the group's responsibility for killing Rajshahi University professor Rezaul Karim for "calling to atheism" in Bangladesh," it said in a tweet.
Also Read
Earlier, Rajshahi's police commissioner Mohammad Shamsuddin told reporters at the scene that the "technique of the murder suggested it could be an act of Islamist terrorists."
An investigation into the killing is on.
Meanwhile, angry students and teachers of the university rallied in the campus demanding immediate arrest of culprits.
Siddiquee's colleagues said he was involved in cultural activities in the campus and used to play flute and sitar.
"He was not known for affiliation for any political party... He had a progressive outlook that might have earned him the wrath of reactionary (Islamist) forces," professor of mass communication department of the university Dulal Chandra Biswas told PTI over phone.
Two years ago, another Rajshahi University teacher AKM Shafiul Islam was similarly murdered. Though his murder was initially claimed by radical group 'Ansaral Islam', police later ruled out that possibility, saying he was murdered due to personal rivalry.
But some years ago, two more professors of the state-run Rajshahi University had been killed.
There have been systematic assaults in Bangladesh in recent months specially targeting minorities, secular bloggers, intellectuals and foreigners.
Last year, four prominent secular bloggers were killed with machetes, one inside his own home.