People in Bangladesh are fighting back.

The couple were on a bicycle rickshaw, returning from a book fair, when two assailants stopped and dragged them on to the pavement before striking them with machetes, local media reported, citing witnesses.

Hundreds of protesters rallied in Dhaka to denounce the murder, chanting slogans including “we want justice” and “raise your voice against militants”.

Imran Sarker, the head of the Bangladesh bloggers’ association, said the protests would continue until those responsible were apprehended. “Avijit’s killing once again proved that there is a culture of impunity in the country,” Sarker told Agence France-Presse. “The government must arrest the killers in 24 hours or face non-stop protests.”

Warning if you read this article: there’s a photo of Rafida Ahmed Banna on a stretcher, soaked in blood. It’s a bit of a shock to see if you’re not expecting it.

Police have launched an inquiry and recovered the machetes used in the attack but could not confirm whether Islamists were behind the incident.

But Roy’s father said the writer, a US citizen, had received a number of “threatening” emails and messages on social media from hardliners unhappy with his writing. “He was a secular humanist and has written about 10 books,” Ajoy Roy told AFP.His most famous work was Biswasher Virus (Virus of Faith).

The Center for Inquiry, a US-based charity promoting free thought, said it was “shocked and heartbroken” by the brutal murder. “Dr Roy was a true ally, a courageous and eloquent defender of reason, science, and free expression, in a country where those values have been under heavy attack,” it said in a statement.

We can’t afford to lose true allies. There aren’t nearly enough of us.

Roy’s killing also triggered strong condemnation from his fellow writers and publishers, who lamented the growing religious conservatism and intolerance in Bangladesh.

“The attack on Roy and his wife, Rafida Ahmed, is outrageous. We strongly protest this attack and are deeply concerned about the safety of writers,” said Sarker.

Pinaki Bhattacharya, a fellow blogger and friend of Roy, claimed one of the country’s largest online book retailers was being openly threatened for selling Roy’s books.

“In Bangladesh the easiest target is an atheist. An atheist can be attacked and murdered,” he wrote on Facebook.

Atheist blogger Ahmed Rajib Haider was hacked to death in 2013 by members of a little-known Islamist militant group, triggering nationwide protests by tens of thousands of secular activists.

So the government acted to protect the rights and freedom and lives of the atheist bloggers, right?

No.

After Haider’s death, Bangladesh’s hardline Islamist groups started to protest against other campaigning bloggers, calling a series of nationwide strikes to demand their deaths, accusing them of blasphemy.

The secular government of the Bangladeshi prime minister, Sheikh Hasina, reacted by arresting some atheist bloggers.

So murdering atheists is ok, while being atheist is a crime. Thanks, BossGod.

The government also blocked about a dozen websites and blogs to stem the furore over blasphemy, as well as stepping up security for the bloggers.

On Friday Sarker said: “Communal and militant groups have threatened the very spirit of our nation. Yet instead of crushing them, the government was keen on appeasing them by arresting secular bloggers.”

But none of this has anything to do with “true Islam.” It’s all impostors and usurpers.