A day after Prof Muhammad Zafar Iqbal survived a knife attack in Sylhet, counterterrorism officials said the youth who carried out it could be a member of banned militant outfit Ansar al Islam.

The attack on Prof Iqbal, a faculty member of Computer Science and Engineering department at Shahjalal University of Science and Technology (SUST), matches the pattern seen earlier in missions of Ansar al Islam, they said.

"Analysing the nature of the attack and from our experience gathered in counterterrorism operations, we can say that this could be an act of Ansar al Islam," said a senior official of Counter Terrorism and Transnational Crime unit of DMP, requesting not to be named.

The weapon seized from the place of occurrence is a commando knife, which is mentioned in the outfit's literature titled “easy strategy for killing”, he said.

"Similar knives were recovered earlier in the outfit's dens," added the official, who is involved in probing the attack.

Foyzur Rahman, a youth aged about 25, was caught red-handed after he stabbed Prof Iqbal during a programme on the university campus around 5:30pm on Saturday.

He told the Rapid Action Battalion that he considered Prof Iqbal an enemy of Islam, said Lt Col Ali Haydar Mohammad Azad, commanding officer of Rab-9.

The suspect also claimed he acted alone but Rab didn't buy it, the CO said early yesterday, adding they were investigating if he was involved with any radical group.

Talking to The Daily Star, another CTTC investigator said Foyzur appears to be a trained operative and most possibly he is linked to Ansar al Islam.

Previously known as Ansarullah Bangla Team (ABT), Ansar al Islam began gaining strength in 2013-14 and started selecting targets by monitoring social media and hacking them to death.

The government banned ABT in May 2015 but the radical group by that time had claimed responsibility for 13 attacks in which 11 individuals including writers and bloggers, one publisher and two LGBT activists were killed.

Currently, police sources say, Ansar al Islam is active mostly in cyber space, attracting potential radicals.

Prof Iqbal was among the 15 eminent persons mentioned in Ansar al Islam's hit list recovered by law enforcers in 2017. Another hit list recovered by police in 2016 from a JMB den in Bogra had also contained his name.

Officials believe Ansar al Islam has a stronghold in SUST and many former students got involved with the outfit.

In primary interrogation, Foyzur said that he believed in militancy, Lt Col Ali Haydar of Rab-9, told reporters at his office yesterday afternoon. "But we aren't sure which organisation he belongs to."

The suspect was a madrasa student and did not continue study after passing Dakhil exam, said the Rab official.

A case was filed accusing Foyzur and five other unnamed people, Shafiqur Rahman, officer-in-charge of Jalalabad Police Station, told The Daily Star.

Foyzur, a resident of Sheikhpara of Kumargaon area in Sylhet Sadar upazila, was kept at MAG Osmani Medical College Hospital under police custody yesterday.

His parents, who fled their house on Saturday evening, an hour after he attacked Prof Iqbal, have surrendered to police, officials say.

“Foyzur's father Atiqur Rahman and mother Minara Begum surrendered at Jalalabad Police Station around 10:45pm [yesterday],” he said.

Police also detained his uncle Fazlur Rahman from a house adjacent to his home at Sheikhpara, an area near SUST.

Besides, Rab detained three, including Abdul Kahhar, another uncle of Foyzur, from Jagadal village in Sunamganj's Dirai upazila. They did not disclose the identities of the other two “for the sake of investigation”.

Raiding Foyzur's house, Rab and police seized some books, CDs and several other things.

The SUST authorities yesterday formed a three-member probe committee headed by Prof Abdul Gani, dean of social science faculty.

'OUT OF DANGER'

A writer revered by students across the country, Prof Iqbal was flown to the capital by an air ambulance and admitted to Combined Military Hospital (CMH) in Dhaka on Saturday midnight.

"He [Prof Iqbal] is now totally conscious and out of danger,” said Maj Gen Munshi Md Mojibur Rahman, chief cardiac surgeon and consultant surgeon general of Bangladesh Armed Forces.

Maj Gen Munshi is leading a five-member medical board that evaluated Prof Iqbal's condition yesterday morning.

"He is now in intensive care unit,” he said, adding that the authorities strictly restricted visitors to ensure his quick recovery and prevention of infection.

"There are four small injuries in the back of his head, one in his back and another in the left hand.”

Replying to a query whether the skull was hit, the doctor replied in the negative.

Prof Iqbal had wounds only in his skin and muscle and needs to stay a couple of days more in the hospital, he said.

"We gave him liquid food in the morning and he took it. There is no injury in his abdomen.”

Minutes after the briefing of CMH doctors yesterday, Prof Iqbal's wife Prof Yasmeen Haque expressed hope that her husband will recover quickly and return to his beloved campus.

"We want him to get well soon and quickly return to the campus," she told reporters at CMH.

Yasmeen, who is also a SUST professor, said her husband made the first phone call to her after the attack and informed her of the matter.

"He said 'I have been attacked but I am fine. I am being taken to the hospital'.

She quoted him as saying, "I did not want you or our daughter to know of the attack from television channels and that is why I called you first. I am bleeding profusely.”

Prof Iqbal also asked his wife to talk to his students and appease them. "Make sure that they do not get agitated,” she quoted him as saying.

She thanked Prime Minister Sheikh Hasina, doctors in Dhaka and Sylhet.

Terming the incident unfortunate, she said police have long been providing them with adequate security. “I do not feel that the government should be immediately blamed for the incident.”

On the threats the couple received on several occasions, Yasmeen said. “We have even been sent shrouds. But should I stop doing everything and live like a prisoner? I do not think so.”

She added, "I am requesting friends, family and well wishers not to meet him yet. I am not meeting him either.”

Also yesterday, Home Minister Asaduzzaman Khan claimed there was no lack in the security of Prof Iqbal.

"There was no lapse in the security measures during the attack on Professor Dr Zafar Iqbal .... Police have already arrested the attacker," he said, speaking at a function in the capital.

However, two police constables have been withdrawn due to their negligence while providing security to Prof Iqbal, a senior official in Sylhet said.

Abdul Wahab Miah, additional deputy commissioner of Sylhet Metropolitan Police, said the two were withdrawn yesterday night. He did not disclose their identities.

[Our Sylhet Correspondent Dwoha Chowdhury contributed to report]