Abdul Raqib Amin, who was brought up in Aberdeen, featured in an online video last month alongside two men from Cardiff, urging Western Muslims to fight and join the Islamic State in Iraq and Greater Syria (Isis) group.
In an interview with ITV’s Good Morning Britain yesterday, he described the moment he left the UK as “one of the happiest” of his life.
Amin said: “I left the UK to fight for the sake of Allah, to give everything I have for the sake of Allah.
“One of the happiest moments in my life was when the plane took off from Gatwick airport. I was so happy – as a Muslim you cannot live in the country of kuffars (non-believers).
“I left the house with the intention not to go back. I’m going to stay and fight until the khilafah (rule of Islam) is established or I die.”
He is identified as Brother Abu Bara al Hindi in the recruitment video which was posted in June.
Amin was educated in Aberdeen after moving to Scotland from Bangladesh but his family left the city a couple of years ago.
In the interview, Amin said he was trained to use weapons and has been involved in “a few” battles.
“I didn’t know how to fight with weapons before, so everyone has to go to a training camp, and after the training camp you go to an Islamic training camp,” he said.
“I’ve been involved in a few combats. The first one I went to, it was against the army – we got two tanks that day.”
Muslim leaders in Aberdeen said they were shocked when he was identified in the video.
Amin revealed that he joined Isis through the internet.
“In Aberdeen mosque there is not one person with the same mentality as me,” he said. “I did not learn my jihad from the Aberdeen mosque.
“I learned that through my own on the internet or whatever. The Aberdeen mosque, they don’t agree with jihad and disagree with all these extremists – if you call them that.”
Over the last two weeks, there has been growing concern over the number of young British Muslims who have joined Isis.
Prime Minister David Cameron claimed that they represent the “biggest threat to national security that exists today”, and the security services have made tracking British jihadists fighting in the region their top priority.
Foreign Secretary William Hague travelled to Iraq at the end of last month and appealed for the country’s political leaders to set aside their differences and unite to combat the threat from Isis.
Friends of Amin have told how he spent his early years in Aberdeen, then moved back to Bangladesh with his family for a time before returning to the city about five years ago. He then moved to England last year.
His former schoolfriends from Aberdeen’s St Machar Academy have described how Amin changed after going abroad.
One former friend, who still lives in the city, said: “I’m sad that the guy I used to hang about with and thought I knew so well is the guy I’m now watching saying these things. It’s scary. He must have been completely brainwashed.”
Meanwhile, Isis has seized huge swathes of territory in northern Iraq and neighbouring Syria, murdering hundreds of prisoners in the process.
The rebels control Iraq’s second city, Mosul, and are pledged to building an extremist Sunni Muslim state straddling the border between the countries.
Iraq’s Shia Muslim-dominated government and army have so far proved powerless to stop them.