At 14-years-old, schoolboy Umar Fidai was brainwashed into thinking blowing himself up in a crowd would get him into paradise.
When his suicide bomb jacket failed to completely detonate, instead blowing off his left arm and tearing open his abdomen, the care shown by doctors who treated him made him realise he was wrong.
The teenager is now in custody after the attack at a Pakistani shrine in early April that killed about 40 people, including another schoolboy suicide bomber named Ismail.
Umar said he now regrets the bombing which was carried out after being lured into training with the Taliban.
"I am so grateful, because I have been saved from going to hell. I am in a lot of pain, but I know there are many people in hospital even more severely injured than me and I am so sorry for what I did and for what Ismail did," Umar told the BBC.
"We did a very bad thing by killing children and old men and women. I now realise suicide bombing is un-Islamic. I hope people will forgive me."
Umar said a member of the Taliban would approach him on the way to school in his hometown, close to the border of Afghanistan, and tell him there was no point in learning.
"He told me that nothing was better than paradise, and that you could earn that by killing non-believers."
"The Taliban prayed all the time and read the Koran, so I thought they were good people. My heart told me to go and train with them."
Umar said he would be blindfolded and taken to training sites, where he learnt how to operate weapons and explosives with three other schoolboys.
He said he and Ismail were told their attack would be on non-believers in Afghanistan, but they instead arrived at a shrine in Pakistan, where extremists believe worship is "un-Islamic".
The plan was for Ismail to detonate his bomb in the shrine, while Umar would wait for ambulances to come so he could blow himself up nearby.
"All I was thinking was that I had to detonate myself near as many people as possible. When I decided it was the right time, it was a moment of happiness for me.
"I thought that there would be a little bit of pain, but then I would be in heaven."
Umar said he hasn't heard from his family since and lives in fear of the Taliban.
"I know my mother and my younger sisters, in North Waziristan, would know what's happened and they must be very upset. I just want to apologise to my mother. But at the time I detonated myself, thoughts of my family were not in my mind, I was only thinking about what the Taliban had taught me."
