Labour MP Jo Cox has died after being shot three times in the street in her constituency of Birstall, West Yorkshire.
The 41-year-old was outside the village's library this morning, where she regularly held advice surgeries, when a man approached and shot her three times.
Witnesses also reported seeing the man attack her with a knife and there are unconfirmed reports that claim he shouted "Britain First" during the attack.
Cox, a mother-of two, was airlifted to Leeds General Infirmary where she died of her injuries this afternoon.
Her husband shared this picture of her when she was taken to hospital:
He released this powerful statement in the wake of her death:
"Today is the beginning of a new chapter in our lives. More difficult, more painful, less joyful, less full of love. I and Jo’s friends and family are going to work every moment of our lives to love and nurture our kids and to fight against the hate that killed Jo.
Jo believed in a better world and she fought for it every day of her life with an energy, and a zest for life that would exhaust most people.
She would have wanted two things above all else to happen now, one that our precious children are bathed in love and two, that we all unite to fight against the hatred that killed her. Hate doesn’t have a creed, race or religion, it is poisonous.
Jo would have no regrets about her life, she lived every day of it to the full."
Speaking before he learned of her death, Shadow Police Minister Jack Dromey said: "She's one of the most decent women ever to enter the House of Commons. An outstanding champion of her constituents.
"A great champion for all that is best in Britain, and today our thoughts are with her."
Labour leader Jeremy Corbyn has said that the "whole of the Labour family" is in shock at her death.
"Jo Cox had a lifelong record of public service and a deep commitment to humanity," he said.
"[Jo] died doing her public duty at the heart of our democracy, listening to and representing the people she was elected to serve. It is a profoundly important cause for us all."
Jeremy Corbyn and Deputy Leader of the Labour Party Tom Watson were among the mourners at a Parliament Square vigil held in her memory on Thursday evening.
A 52-year-old man was arrested at the scene, West Yorkshire Police confirmed. He has been named locally as Tommy Mair.
Chief Constable Dee Collins said: "Just before 1pm today Jo Cox, MP for Batley and Spen, was attacked in Market Street, Birstall. I am now very sad to have to report that she has died as a result of her injuries. Before going into further detail, I would like to express our deepest sympathies to her family and friends at this tragic time.
"Jo was attacked by a man who inflicted serious and sadly ultimately fatal injuries. There was a subsequently an attack on a 77-year-old man nearby who has sustained injuries that are non-life threatening. Shortly afterwards a man was arrested nearby by police officers. Weapons, including a firearm, have also been recovered.
"At 1.48pm Jo was pronounced dead by a doctor working with a paramedic crew who was treating her injuries. This is a very serious investigation with a large number of witnesses that are being spoken to by police at this time. There is a large and significant crime scene. There is a large police presence in the area. A full investigation is underway to establish the motive of this attack.
"There are specially trained officers with Jo's immediate family who are fully aware of what has taken place. And we would ask the media to respect their privacy at this difficult time. Additional officers are working with the local community this evening, in order to provide support and reassurance to our communities.
She added: "Clearly as our inquiry is at a very early stage, and we have an individual under arrest, we are not in the position to discuss any motive at this time. We are not looking for anyone else in connection with the incident."
All EU referendum campaigning was suspended following news of the attack. Home Secretary Theresa May said: “It is entirely appropriate that all campaigning for the referendum has been suspended.
“All of us are united in the deep sadness of the loss of one of our brightest and most popular Westminster colleagues.”