Unidentified assailants hacked a Hindu man to death in front of his tailoring business in central Bangladesh on Saturday, police said.
Nikhil Chandra Joardar, 50, was repeatedly attacked by three men with sharp weapons and left for dead, officer Abdul Jalil said, citing accounts by local residents.
The assailants arrived on motorbike, dragged the victim from his shop and then hacked at him on the head and neck before fleeing the scene, he said.
The killing occurred in Tangail district, about 100 kilometres north-west of the capital Dhaka.
Islamic State, the radical Sunni Islamic group that controls large swathes of Iraq and Syria, reportedly claimed responsibility.
US-based SITE Intelligence Group tweeted that the Islamic State had murdered Joardar for undermining Islam and its prophet.
The claim, however, could not be verified independently.
Saleh Mohammad Tanvir, chief of the district police, said the motive for the killing was not yet known, but that it was similar to recent attacks on rights activists, a university teacher and secularist bloggers.
Two gay rights activists were killed at an apartment in Dhaka by suspected Islamist militants on Monday while an English professor was hacked to death near his home in northern city of Rajshahi on April 23.
Five secularist bloggers and a publisher were killed in similar attacks in majority-Muslim Bangladesh in recent years. Islamic State and Ansar al-Islam, an affiliate of al-Qaeda, claimed credit for those attacks.
Abdul Latif, a local government official in the Gopalpur sub-district where the attack took place, said Joardar had been arrested in 2012 after a local religious school teacher accused him of making derogatory remarks about Islam and the prophet Mohammed.
Joardar was released 24 days after he was arrested, said Latif, but added that it was not clear whether his alleged anti-Islam comments prompted the assailants to carry out the attack.
Arati Rani, wife of the slain tailor, told local media that her husband never spoke against any religion.