The man who allegedly attacked and killed British MP Jo Cox reportedly had links to an American neo-Nazi group, with British media naming him as local man Tommy Mair.
The Southern Poverty Law Centre said he was a supporter of a neo-Nazi group based in the United States and had what it called a long history with white nationalism.
"According to records obtained by the Southern Poverty Law Centre Mair was a dedicated supporter of the National Alliance (NA), the once premier neo-Nazi organisation in the United States, for decades," the US-based legal advocacy group said on its website.
The group said he had spent more than $US620 on reading material from the National Alliance, a group which called for the creation of an all-white homeland and eradication of Jewish people.