The body of publisher Faisal Arefin Dipan lies on a table at the morgue in the capital city of Dhaka, Bangladesh, Oct. 31, 2015. Getty Images/Munir Uz Zaman

UPDATE: 1:01 a.m. EST -- A local arm of al Qaeda claimed responsibility for an attack on two publishers in Bangladesh, the New York Times reported Sunday, citing the SITE Intelligence Group. The men who were targeted published articles critical of fundamentalism in Islam.

Faisal Arefin Dipan died of his wounds immediately after the attack, the report added, citing local police said, while the other, Ahmed Rahim Tutul, was reportedly in critical condition late Saturday.

Original story:

In Bangladesh, small groups of Islamist radicals have systematically sought out and killed four secular bloggers and writers since the start of the year. The first attack came in February, when machete-wielding attackers killed Avijit Roy in the capital city of Dhaka. Roy was a writer who spoke freely against religion and violence.

On Saturday, assailants carried out another gruesome installment. Faisal Arefin Dipan, a publisher who had supported the work of Roy, was killed in his office in Dhaka. When Dipan’s father found him, his throat was slashed, and he was lying upside-down in a pool of blood, Agence France-Press reports.

It was a bloody day in the capital, as another publisher of Roy’s named Ahmedur Rashid Tutul and two bloggers, Ranadipam Basu and Tareq Rahim, were victims in a separate attack that left them critically injured.

A local group called Ansarullah Bangla Team, which is connected to al Qaeda, has claimed credit for all the attacks. It posted a statement on social media that said the publishers had supported work that dishonored the Prophet Muhammad and the religion of Islam, Time reports.

The group's actions are seen as a threat to free speech in the predominantly Muslim country and a form of retaliation against 2013 protests that pushed for harsh punishments for former Islamist leaders who were convicted of war crimes. Roy was an active leader in voicing those demands, as were the four other victims to date.

Bangladeshi Prime Minister Sheikh Hasina has condemned the attacks but also criticized people such as Roy and Dipan who do not declare a religion, or choose to speak out against the faith of others. On Saturday evening, hundreds of activists marched in the streets of Dhaka to call on the government to do more to protect writers, bloggers and publishers the group has publicly identified as targets.