The man arrested over the killing of the MP Jo Cox purchased books from a US-based neo-Nazi group, including guides which promoted the eradication of the Jewish people.
The Southern Poverty Law Center (SPLC) has published receipts that appear to show Thomas Mair bought books from the National Alliance on how to build homemade guns and explosives.
Other receipts suggest he purchased Ich Kampfe, an illustrated handbook issued to members of the Nazi party in 1942.
According to the American anti-hate campaign group, the receipts, some dating back to the 1990s, show Mair spent more than £436 on literature from the white nationalist group.
He bought books that instructed readers on the “chemistry of powder and explosives”, “incendiaries” and an Improvised Munitions Handbook.
The handbook includes detailed instructions on constructing a pipe pistol using parts available in DIY stores.
Witnesses to the shooting of Mrs Cox claimed the suspect shouted “Britain first” during the attack.
The far-right party Britain First released a statement after the attack to say it was not involved in the and “would never encourage behaviour of this sort”.