Image: Antti Pylväs / Yle

A man who left Finland to join the terrorist group Isis was the son-in-law and business partner of the imam of the Oulu-based Islamic Society of Northern Finland, Yle's investigative journalism programme MOT reported on Monday.

As part of a programme on terrorism fundraising in Finland, MOT journalists found that those who have left the country to join Isis earned money through a variety of illegal and legal means, ranging from tax fraud to running pizzerias.

One of them was Taz Rahman, a Bangladeshi-born man who joined Isis and was later reported to have died in Syria.

He had co-owned a business with Oulu Imam Abdul Mannan, who is also from Bangladesh.

According to leaked Isis documents, Rahman joined Isis in the summer of 2014 and went to Syria with his wife, the imam's daughter.

Before his departure, Rahman ran two companies in Finland. One was a pizzeria that still operates in Helsinki. His former business partner declined to be interviewed, saying only that Rahman had failed to pay money he owed.

Rahman's second business was registered as a food kiosk at the address of the Oulu mosque, located in a nondescript building a couple of blocks from the Lutheran Cathedral in central Oulu.

Mannan, who is an Islamic instructor, served as a deputy city councillor for the Social Democratic Party from 2012 to 2017. According to the newspaper Ilta-Sanomat, Mannan moved to Oulu from Bangladesh in 1992 to study geology, earning a doctoral degree from the University of Oulu in 2002.

"He's solely responsible"

Interviewed in English by MOT, Mannan denied several times that he personally knew anyone who had been radicalised.

"I know each and every person. We don't have any extremists here," he said in the interview, to be broadcast on Yle's TV1 on Monday evening, and already viewable on its Areena web service.

Asked if he knew Rahman, Mannan replied, "I told you that I don't want to answer these things, please."

Pressed on the issue, he said, "He is my relative, my daughter's husband, that's all."

MOT reports that Rahman and Mannan's daughter went to Syria together in 2014, and that they had children together.

Mannan said he did not know that they were going before they left.

"It's the person, individual case, who is responsible for this. So if someone takes some decision for his own and without consulting us, so he's solely responsible for that," he said.

In May 2017 Isis announced Rahman's death and published a photo of him, saying that he had worked as physical therapist for the group.

Repeated vandalism

Mannan said he does not know whether his daughter is still in Syria, and has not heard from her in nearly two years.

"I told police; it is their responsibility to find out. Not only her, there might be some more Finnish nationals, so they are trying," he said.

"All of them are members of this society," he added. "So when they come back, they will be treated in a nice way. They will be rehabilitated and [we will] let them live a normal life. I hope it will work."

In January, Mannan told Yle that the mosque had been vandalised for a ninth time within a year when a smoke bomb was thrown in, breaking a window.

The Muslim population of Oulu is estimated to be over 3,000. Some 1,000 people from more than 20 countries attend events at the mosque.

2 April 2019 at 9:53am: Edited to reflect that Rahman joined Isis in the summer of 2014 and went to Syria with his wife, the imam's daughter.