JUST NUTS:

Panorama has spent months speaking exclusively with friends of the bombers to try to understand the roots of their radicalisation.

The programme discovered that Tamerlan Tsarnaev possessed articles which argued that both 9/11 and the 1995 Oklahoma City bombing were government conspiracies.

Another in his possession was about "the rape of our gun rights".

Reading material he had about white supremacy commented that "Hitler had a point".

Tamerlan Tsarnaev also had literature which explored what motivated mass killings and noted how the perpetrators murdered and maimed calmly.

There was also material about US drones killing civilians, and about the plight of those still imprisoned in Guantanamo Bay.

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