Isis has claimed responsibility for the murder of a professor in Bangladesh for supposedly “calling to atheism”.

Rezaul Karim Siddique, 58, was on his way to the Rajshahi University where he worked as an English teacher when he was viciously attacked.

Police have said the incident, which took place on Saturday, is similar to others in recent months by suspected Islamic militants.

In a propaganda statement, Isis, also known as Islamic State and Daesh, said its fighters had carried out the murder.

Deputy police commissioner Nahidal Islam, said the attackers used sharp weapons to kill Professor Siddique and then fled the scene.

His brother, Sajidul Karim Siddique, described the victim as a “very quiet and simple man” who was focused on studying and teaching. He also led a cultural group and used to edit a literary magazine.

“So far as we know, he did not have any known enemies and we never found him worried. We don’t know why it happened to him,” he said.

Parallels have been drawn to the murders of four secular bloggers who were killed with machetes last year.

The four men had appeared on a list of “atheist bloggers” circulated by the Ansurallah Bangla Team – purportedly an affiliate of al-Qaeda – in 2013. Local militants claimed responsibility for their deaths.

In September 2015 Isis claimed responsibility for the death of an Italian citizen in the Dhaka, the country’s capital.

In addition, at least three other professors at Rajshahi University have been killed in recent years, all allegedly by Islamist groups.

The government in Bangladesh has previously dismissed suggestions that Islamist terrorist attacks take place in the country, claiming Sunni extremists are simply not present. It has been criticised for a lack of action to address the problem.

In November hundreds of people took to the streets in Dhaka to protest about the on-going attacks after publisher Faisal Arefin Dipan was murdered.

Professor Anwar Hossain, a former vice chancellor at the Jahangimagar University, expressed the views of many when he said: “After every killing, statements are given by the government and law enforcement agencies. But they can neither arrest any killer nor complete the investigation,” he said, according to the Dhaka Tribune.

War crimes trial campaigner Muntassir Mamoon, who also spoke at the protest, said: “Such lenient statements from the government are encouraging the killers.”