The Parsons Green 'bomber' has told a court he made up a story about being kidnapped by Islamic State because he wanted to study in Britain to become the new David Attenborough.
Ahmed Hassan arrived in Britain in October 2015 and told immigration officials he had been forced to train 'to kill' by Isis, the Old Bailey has heard.
But the 18-year-old Iraqi asylum seeker has now told jurors that he was never taken prisoner by Isis and had not had any contact with the terror group.
Asked why he made up the story, the media student told the court: 'Because I came from a wealthy, safe area in northern Iraq in Kurdistan and if I told the truth, my only reason to leave the country was to further my studies ... I felt I had to make up something strong.
'In the Jungle in Calais, people used to talk about these things and make up stories. I never came across a refugee who said he would tell the truth when he arrived in the country.
'I wanted to go to university and my ultimate goal was to become a wildlife photographer like David Attenborough.'
On September 15 last year, Hassan planted 400g of homemade explosives and shrapnel on a District line Tube timed to go off when it reached the West London stop, the court has heard.
When he was picked up at the port of Dover the following morning, he told police he had made the bomb, which only partially exploded on the packed rush hour service.
Giving evidence in his defence, Hassan told how he was born in Baghdad.
His mother died when he was young and his taxi driver father was killed in an explosion in 2006, he said.
'So far as I'm aware, I was told that he died in an explosion while he was working as a taxi driver. He used to go to work and come back evenings and then he did not come back.
'It was very difficult. I did not understand what was going on. I was in a state of confusion because of fighting, because of bombing.'
Hassan told jurors he moved to northern Iraq with his uncle and older brother, and from the age of 12 worked ferrying goods such as vegetables across the border with Iran.
The defendant said he decided to leave Iraq because he wanted 'a better life'.
He said: 'I wanted studying, I wanted to learn English and there was so much pressure on me to keep on with my job.'
He smuggled himself to Britain by train and on a lorry at the age of 16, he said.
Hassan, wearing a white open-necked shirt under a dark blue jumper, confirmed his name when asked by his barrister Tim Moloney QC today.
Speaking with his head bowed, he confirmed he would not be using an interpreter but said he may need to ask for questions to be repeated or rephrased.
He said: 'My English is not perfect and my accent is not perfect either.'
He told the court he has one older brother, aged 25, who is still in his native country of Iraq.
Asked if his parents were still alive, Hassan said: 'No, passed away.'
He said he was too young to remember his mother, but said he remembered his father, who died when Hassan was aged seven.
Hassan told the jury: 'So far as I am aware I was told that he died in an explosion while he was working as a taxi driver.'
Hassan said he left Iraq because he wanted 'a better life'.
He described himself as a good student.
The 18-year-old said: 'I was very good. I was very clever.'
Asked by Mr Moloney if he had ever been mistreated by IS, Hassan said: 'No, I have never had any contact with IS at all.'
He said it had been 'fairly easy' to cross the border from Iraq to Turkey.
Hassan had stayed in Istanbul for about two weeks before moving on to Italy, where he said he had not been well treated.
He said: 'I was abused by the Italian authorities. They were not very nice with me, so I left.'
Hassan travelled from there to Paris, then to the Jungle camp in Calais, before entering the UK on a lorry.
Hassan told jurors he spent three days in hospital because he 'considered to commit suicide'.
He said he used to snap pens at college because he would get 'angry' and needed a way to 'empty myself' and have a 'peaceful moment'.
Hassan told jurors he enjoyed studying photography when he was at Brooklands College in Weybridge. He described himself as 'very shy'.
Hassan said: 'I enjoyed being behind the camera rather than in front of the camera.'
The court was shown a series of pictures taken by Hassan, some of deer in Richmond Park, South West London.
He said he eventually wanted to be a wildlife photographer.
Jurors also saw two short animations, one of which was a carrot in the guise of a character walking along, both created by Hassan.
He added: 'I was part of a project that I was going to finish this year. I was going to make a short cartoon.'
Hassan, who was living with foster parents in Sunbury, Surrey, has denied attempted murder and using the chemical compound TATP to cause an explosion that was likely to endanger life.
The trial continues.
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