Haider, a self-proclaimed atheist, posted his blogs under the pseudonym Thaba Baba, where he questioned the historical authenticity of Islam. The content of his writings were deemed "blasphemous" by religious hardliners, resulting in them demanding blasphemy laws be instituted and that he be killed.^[10][11][12]

On the night of 15 February 2013, Haider was attacked as he was leaving his house in the Mirpur area of Dhaka. His body was found lying in a pool of blood,^[13] mutilated to the point that his friends could not recognise him.^[7] The following day, his coffin was carried bearing the national flag through Shahbagh Square in a public protest by more than 100,000 people.^[14] Prime Minister Sheikh Hasina visited his family in Palashnagar, Dhaka, and promised action.

On 2 March, the Bangladesh Detective bureau arrested five members of the newly formed extremist organisation Ansarullah Bangla Team for the murder.^[5] The organization was an offshoot of the Islami Chhatra Shibir, a student wing of the Jamaat-e-Islami political party. The group takes its ideology from Anwar Al-Awlaki, a Yemen-based Al-Qaeda islamic-fundamentalist who was killed in 2011. Detectives said that the attack was masterminded by the Islamic Chhatra Shibir leader 'Rana' from Jamaat-e-Islami's youth wing,^[15][16] who had not been located two months after the event.^[17]

The five students, Faisal bin Nayeem alias Dwip, Maksudul Hassan Anik, Ehsan Reza Rumman, Naim Sikder Irad, and Nafis Imtiaz, confessed to the crime in front of a magistrate.^[15] The students came from affluent backgrounds.^[18] The day before the murder, Anik, Raza and Irad played cricket in the grounds in front of Haider's house, as part of the "Intel team".^[15] Two of the masterminds of the attack were sentenced to death.^[19]

The incident occurred at the peak of the 2013 Shahbag protests in Bangladesh. Though attacks against atheist and other secular-minded writers were not a new phenomenon in Bangladesh, the death of the 30-year-old architect and Shahbag activist brought the struggle of Bangladeshi freethinkers greater prominence.^[20]

Haider's murder is seen as part of a larger attack against atheist and secularist bloggers in Bangladesh. Islamic groups had been rallying for a blasphemy law along the lines of the Blasphemy law in Pakistan.^[21] A month before the attack on Haider, blogger Asif Mohiuddin was attacked outside his house by four youths,^[22] also from the Ansarullah Bengali Team. Although seriously injured, Asif survived. His attackers were apprehended in April 2013 based on leads from the Haider murder investigation.^[18] Another controversial author, blogger & online activist named Sunnyur Rahman, popularly known as 'Nastik Nobi' (Atheist Prophet) in the blog community, was also stabbed on 7 March 2013.^[23]

In March 2013 Asif's blog in somewhereinblog.net was shut down by the Bangladesh Telecommunication Regulatory Commission. In April, Asif was arrested for "blasphemous" posts,^[24] along with three other bloggers, a move protested by the 2013 Bengali blog blackout.^[25] The crackdown on independent blogs, and the closure of the newspaper Amar Desh, was strongly criticised by Human Rights Watch^[26] and IHEU.^[27][28] Shortly after the bloggers were arrested, Mukto-Mona, an independent site of freethinkers and atheists of mainly Bengali and South Asian descent, issued a statement titled, 'Bangladesh government squishing freedom of speech by arresting and harassing young bloggers inside the country'.^[29] Amnesty International also issued a statement titled, 'Bangladesh: writers at risk of torture’.^[30]

The Center for Inquiry (CFI), requested the US Secretary of State John Kerry "pressure the government of Bangladesh to reverse its policy of arresting atheist bloggers who were critical to religion." They sent a letter to Ambassador-at-Large for International Religious Freedom Suzan Johnson Cook "to do all they can to raise public awareness of this situation." Other influential organisations such as the Free Society Institute of South Africa, Reporters Without Borders, Committee to Protect Journalists, Global Voice Advocacy, and several other bodies also called for the immediate release of the Bangladeshi bloggers and appealed to several foreign authorities to press Bangladesh on the issue.^[31]

Worldwide protest and demonstrations were held on 25 April and 2 May 2013, to put pressure on the Bangladeshi government to free the arrested bloggers. Several humanist groups (including CFU, CFI-Canada, the British Humanist Association, American Atheists, Secular Coalition for America, and Freethinkers of University of Missouri's campus) took part in cities the US, Canada, the UK, and Bangladesh.^[32] Many writers, activists, and prominent intellectuals around the world including Salman Rushdie, Taslima Nasrin, Hemant Mehta, Maryam Namazie, PZ Myers, Avijit Roy, Anu Muhammad, Ajoy Roy, Qayyum Chowdhury, Ramendu Majumdar, Muhammad Zafar Iqbal publicly expressed their solidarity with the arrested bloggers.^[32] Three of the arrested bloggers eventually were released on bail,^[33] however the court denied bail for Asif Mohiuddin and he was sent to prison on 2 June 2013.^[34] He was released after three months but still faces charges.^[35][36]

2015 edit

In 2015 alone, at least five more secular writers and publishers were murdered by Islamists:

1. 26 February: US blogger and author Avijit Roy was hacked to death yards away from the Dhaka book fair.^[37]
2. 30 March: Blogger Washiqur Rahman, who wrote under the pen-name "Kutshit Hasher Chhana" ("ugly duckling") was hacked to death in broad daylight near his home in Tejgaon, Dhaka. Two of the three killers were grabbed by a transgender beggar as they attempted to flee the scene, and detained until police arrived.^[38][39][40]
3. 11 May: Ananta Bijoy Das, 33, a banker and a founder of a group called the Science and Rationalist Council was hacked to death while walking to work in Sylhet.^[41]
4. 6 August: Blogger Niloy Chakrabarti, who had spoken in May to The Guardian about his death threats, was killed by a machete gang in his fifth-floor apartment in Dhaka.^[42]
5. 31 October: Publisher Faisal Arefin Dipan, who had published a widely read book by Avijit Roy, was hacked to death in his office.^[43][44]

In addition, publishers Ahmedur Rashid Tutul and bloggers Ranadipam Basu and Tareq Rahim were severely injured in machete-wielding attacks in 2015.^[45][46]

• Ahmed Rajib Haidar's blog under the name Thaba Baba