Successful execution of a plot to kill writer-blogger Avijit Roy encouraged pro-al-Qaeda militant outfit Ansar al-Islam to hatch another plan to kill publisher Faisal Arefin Dipan last year, police said yesterday.

Motivated by their operation commander and sacked army major Syed Ziaul Haq, Ansar al-Islam members killed Jagriti Prokashani owner Dipan for publishing books of Bangladesh-born US citizen Avijit, said Monirul Islam, chief of Counter Terrorism (CT) Unit of Dhaka Metropolitan Police.

Monirul made the disclosure hours after the arrest of Moinul Hasan Shamim alias Sifat, whom police identified as a key plotter of Dipan murder. Sifat, who is from Sunamganj, also uses two other names -- Samir and Imran.

Forty-three-year-old Dipan was hacked to death inside his office on the second floor of Aziz Cooperative Super Market in the capital's Shahbagh on October 31.

A team from the Detective Branch of police arrested 24-year-old Sifat, who had a bounty of Tk 2 lakh on his head, near Cherag Ali Market in Tongi around 7:30pm on Tuesday.

Police announced bounties of Tk 18 lakh for Sifat and five other militants on May 19.

Monirul said five militants led by Sifat took part in Dipan killing. They had kept a watch on Dipan's movement for several days before carrying out the attack.

The militants had been motivated and trained for a month before the incident, said Monirul, also an additional commissioner of the DMP.

They carried machetes and firearms. But they didn't use the firearms as they managed to carry out the killing mission without any obstacles.

“In primary interrogation, the arrestee told police that sacked army major Zia was the mastermind behind the killing. He motivated them to murder Dipan,” said Monirul.

Sifat admitted to police that he was involved in several incidents, including the murder of a blogger and student of Shanto-Mariam University of Creative Technology in Savar, added the CT Unit chief.

Seeking anonymity, a top official at the unit said the sacked army major, who has a bounty of Tk 20 lakh on his head, met the militants at least twice before Dipan's murder. 

In order to inspire the militants to carry out the attack, Zia told them that he had sacrificed his “job and honour for jihad”, said the official.

Police said the militants rented several houses for carrying out the mission. They took training at a house in Tongi and later shifted to another house in Mohakhali where they stayed till the execution of the murder plot.

They left the house after the synchronised attacks on Dipan, and publisher Ahmedur Rashid Tutul and two blogger-writers in Mohammadpur on October 31, said police.

Tutul and the two blogger-writers survived the attack. 

Following Avijit's murder on the Dhaka University campus on February 26 last year, the militants targeted Dipan and Tutul, both of whom published Avijit's books, according to police.

In an email to different media outlets after the attacks, a group identifying itself as “Ansar al-Islam (AQIS Bangladesh),” claimed responsibility for the twin incidents.

“These secular and atheist publishers waged war against the religion of Islam in every possible way,” it said, threatening to annihilate anyone who would dare stand against Islam.

Chhatak police said Sifat was earlier arrested from Gobindaganj Bazar while handing out leaflets of banned militant outfit Hizb ut-Tahrir in 2010. He was a student of Madan Mohan College at that time.

Sifat was accused in a case filed with Chhatak Police Station under the Anti-Terrorism Act, reports our Sylhet correspondent.

Police said they were looking into whether Sifat had links with any political parties. 

Yesterday, a Dhaka court placed Sifat on a six-day remand after police produced him before it.

Talking to this correspondent yesterday, Dipan's father Prof Abul Kashem Fazlul Haque said he learnt about Sifat's arrest through the media.

“Those who are recruiting people for carrying out militant activities must be brought to book.

“It hurts whenever the memories of my son come to my mind… I will never get him back.”

“I want peace to prevail, and for this, the country's unhealthy political culture must change,” he added.  

POLICE FOR BANNING ANSAR AL-ISLAM

Police would write to the home ministry for banning militant outfit Ansar al-Islam, said Monirul.

A group of militants, who ran the blog site “Ansarullah Bangla Team”, formed Ansar al-Islam in September 2014 following a call purportedly from al-Qaeda chief Ayman al-Zawahiri for waging an intifada (popular uprising).

The government banned Ansarullah Bangla Team as a militant organisation on May 25 last year.

The CT Unit chief said a maulana runs Ansar al-Islam and sacked army major Zia works as one of the coordinators of its operation wing.

Police said the militant outfit has three wings -- dawah, ashkari or operation, and media wings -- under three chiefs.

The members of dawah mainly propagate its ideology and recruit members. The operation wing trains its operatives, who take part in killing missions.

And the third wing spread the news of the attack following the killings or attacks.