The Islamic State fighter known as "Jihadi John" was a cold loner who set himself apart from others, says an IS defector who met him in Syria.

The BBC has spoken to a man who came across Mohammed Emwazi when he first arrived in Syria about two years ago.

Unlike other Britons, Emwazi wanted to appear in IS videos, the man said.

Emwazi, a Kuwaiti-born UK citizen, formerly from west London, has been named as the man in several IS videos where hostages have been beheaded.

Abu Ayman, as he calls himself, is a skinny young man in his 20s, with a ready smile, and a defector from IS, also known as Isis or Isil.

He spoke to us about his encounters with one of the world's most wanted men.

When they met, they were both just ordinary fighters with Islamist groups fighting the Syrian regime.

Foreign fighters - many from Britain - had gathered at a town called Atmeh in northern Syria.

'He was strange'

Atmeh was - and is - a sprawling, desolate refugee camp on a hillside.

But the jihadis took over nearby homes and lived in some comfort.

The Britons called it their "five star jihad" - and they posted Twitter and Instagram snaps to show it.

Abu Ayman visited the "British house" several times.

He said Mohammed Emwazi struck him as odd the first time he met him.

"He was cold. He didn't talk much. He wouldn't join us in prayer," he said.

"He'd only pray with his friends. … the other British brothers prayed with us, but he was strange."

He added: "The other British brothers would say 'hi' when they saw us on the road, but he turned his face away.

"The British fighters were always hanging out together, but he wouldn't join them."

So how did Mohammed Emwazi, the foot soldier, become "Jihadi John", the awful symbol of Islamic State's brutality?

"Isis have professional psychologists," said Abu Ayman.

"They know who to choose from the fighters and how to make them famous.

"Still, there was nothing special about Jihadi John… anyone could have become like him."

He continued: "The emirs give the orders - and in return you get promoted.

"Many brothers joined Isis for new weapons, luxury guns, to drive better jeeps and to show off."

Closely guarded location

Abu Ayman says he left IS after being ordered to murder women and children

I asked him what his former comrades thought of "Jihadi John". "Some love him," he said.

"Some joined Isis after watching and admiring him; they take him as an example.

"Isis play him like a piano. He's a celebrity to attract our Muslim brothers in Europe."

"But," he continued, "some think he is showing off; they think he's being used by Isis.

"They want to defect; they'll run away, as soon as they get the opportunity."

Of course, we can't be certain that Islamic State turned Mohammed Emwazi into Jihadi John, the braying executioner.

Perhaps that side of his personality was always there, and was just brought out by the war.

He would say, no doubt, that he is implementing God's law - and hitting back at Western countries that have carried out air strikes against IS.

We have heard from several reliable sources that IS places great importance on keeping him safe, with his location a closely guarded secret.

He is for them a potent propaganda asset, encouraging other angry young men to come to Syria from Europe to become just like him.