Labour MP Jo Cox is in a critical condition after she was shot in an attack in her constituency near Leeds.
An eyewitness said the 41-year-old mother of two was left lying in a pool of blood on the pavement after her assailant struck in Birstall, West Yorkshire.
Hichem Ben Abdallah said: "He was kicking her as she was lying on the floor."
A second witness reported three shots, including one "round the head area".
Mr Abdallah said that after a bystander intervened, the attacker produced a gun, stepped back and shot her twice.
West Yorkshire Police said a 52-year-old man has been arrested in connection with the attack, which happened near the town's library, where the MP holds her advice surgeries.
Mr Abdallah, 56, was in the cafe next door to the library when he heard screaming and went outside.
After around 15 minutes, the shop owner said emergency services arrived and tended to her with a drip.
Ms Cox's assistant confirmed she had been attacked and said he was trying to get more information from police at the scene.
Mr Abdallah said the weapon looked handmade and that the man who had been wrestling with the assailant continued to do so even after he saw 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."
A police spokesman said: