The man accused of killing UK MP Jo Cox on a street in broad daylight had far-right sympathies, British reports suggest.
The Labour MP and mother of young children was shot, stabbed and then kicked on Thursday afternoon (local time) as she lay on the ground after meeting constituents in the Yorkshire town of Birstall.
A 52-year-old local man, Tommy Mair, has been arrested over her killing.
The BBC is reporting that Mr Mair's name appears on a website linking him to the South African neo-nazi publication, Patriot, and a witness said the attacker twice shouted "Britain First" or "put Britain first" during the attack.
Britain First is a far-right, anti-European Union (EU) party. It has denied any involvement in the killing.
The UK is about to go to the polls on 23 June to vote on whether the country should leave the EU or remain a part of it.
Tributes have flooded in for Mrs Cox, including from UK Prime Minister David Cameron, opposition leader Jeremy Corbyn and US Secretary of State John Kerry.
Mrs Cox's husband Brendan said she would want people "to unite to fight against the hatred that killed her."
Vote Leave and Remain have both suspended campaigning in the EU referendum in light of the attack.
Following her death, dozens of Mrs Cox's friends and colleagues gathered for a vigil at St Peter's Church in Birstall.
Some of the attendees stifled silent tears and held tissues to their faces. The mood was one of shock and sadness.
A candle was lit in Mrs Cox's memory and people of all faiths came to bow their heads.
Cafe owner Clarke Rothwell, who witnessed the attack, said he heard a "loud popping noise that sounded like a balloon burst - a loud balloon."
"When I looked round there's a man stood there in his 50s with a white baseball cap on and a jacket with a gun, an old fashioned looking gun in his hand," he said.
"He shot this lady once and then he shot her again, he fell to the floor, leant over shot her once more in the face area.
"Somebody tried to grab him, wrestling with him and then he wielded a knife, like a hunting knife, just started lunging at her with a knife half a dozen times. People were screaming and running from the area."
Eyewitness Hithem Ben Abdallah, 56, was in a cafe next door to the library shortly after 13:00 BST when he heard screaming and went outside.
""There was a guy who was being very brave and another guy with a white baseball cap who he was trying to control and the man in the baseball cap suddenly pulled a gun from his bag."
After a brief scuffle, he said the man stepped back and the MP became involved.
Mr Abdallah said the weapon "looked handmade" and a man who had been wrestling with the gunman continued even after seeing the gun.
He said: "The man stepped back with the gun and fired it and then he fired a second shot, as he was firing he was looking down at the ground.
"He was kicking her as she was lying on the floor," he said.