How a knock at the door put MI5 suspect Mohamed Aden on the road to joining Isis

Mr Aden was part of a group of north London men who claimed to be facing harassment by the security services

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For Mohamed Aden, life in Britain was not easy. His father left the family home while he was growing up, his grasp of English was poor and he found it hard to earn enough money. Now he is in Syria fighting with one of the Islamist militias, possibly Isis.

I met him in 2009 when he was part of a group of north London men who claimed to be facing harassment by the security services.

Mr Aden, then 25, had been targeted because the police and MI5 believed he was linked to Islamist extremism in Somalia. He said he was simply exploring his own interests in political Islam.

For several months he had suffered in silence, not daring to tell anyone about his contact with UK secret services in case people suspected him of being a spy or a terrorist – he didn’t know which he feared more.

It was only when other members of this group of Kentish Town youth workers complained about similar treatment from the security services that Mr Aden came forward to tell his own story.

He said he had been approached by counterterrorism officers who had tricked their way into his home, and that he had been bombarded with phone calls from the security services.

“One morning there was a knock on the door by the postman,” Mr Aden told me in 2009. “Half asleep, I went to open it. I opened the door slightly and the man said he was a postman, but as soon as he said this he moved to the side and a man and woman from MI5 were standing in front of me. They said, ‘Hi, Mr Aden, we are from MI5. Can we have a moment of your time?’

“I was totally shocked, I was completely angered at the fact that they had lied to me in order to get my door open.

“Before they could say anything else, I angrily told them that how dare they come to my home first thing in the morning and lie to me in order to get me to open the door when I had respectfully opened it for who I thought was a postman.”

The men immediately accused Aden of being involved in terrorist activities.

“When I told them they had got the wrong man, one of the agents called me by a different name. In the middle of the conversation he said, ‘OK, Mr Yusuf.’ I told him, ‘What the hell are you talking about, who is Mr Yusuf?’ I literally ran back to my bedroom and grabbed my passport, I then showed them that it said Mohamed Aden, not Mr Yusuf.

“The agent didn’t even move and the lady [another member of the security services present] began to smile. I began to get very angry, I asked her what was so funny, but she didn’t respond.”

The male officer told Mr Aden that he should co-operate with them otherwise they could make his life very difficult. “They wouldn’t allow me to travel or do anything.” But he told the officers he wasn’t going to help. Mr Aden said he was very worried about his life and for his family.

One of Mr Aden’s friends claimed that even after the publicity around his case the security services continued to take an interest in him. He also found it difficult to escape the public attention his case attracted. He disappeared in 2014 and is now believed to be in Syria fighting for one of the Islamic militant groups.

Of the six Kentish Town men I interviewed in 2009 about their problems with the security services, two joined terrorist groups. The other was Mahdi Hashi, who ended up being captured in East Africa by American officials, who charged him with membership of the terrorist group al-Shabaab. The Home Secretary, Theresa May, has stripped him of his British passport and this week he will be sentenced in an American court.

The remaining four have overcome their difficulties and gone on to resume peaceful lives in Britain.