Colleagues of Labour MP Jo Cox have spoken of their horror and sorrow.
The 41-year-old was shot and stabbed in her constituency in West Yorkshire this afternoon.
Julie Elliott, who represents Sunderland Central, said: "Jo was a truly remarkable woman who will be deeply missed by all who knew her. My thoughts are with her family tonight."
Washington and Sunderland West MP Sharon Hodgson said: "I'm heartbroken my thoughts are with Brendan & their kids. @Jo_Cox1 was an amazing mum, a brilliant MP, so talented, it's so wrong, RIP Jo x"
Hartlepool MP Iain Wright said: "What a loss of such a talent. Most importantly, the loss of a loving wife and mother. Thoughts and prayers with Jo's family. RIP Jo."
South Shields MP Emma Lewell-Buck said: "Devastated - Jo a beautiful, kind and intelligent woman, will miss her terribly. Thoughts and prayers with her family."
Houghton and Sunderland South MP Bridget Phillipson earlier described the incident as "horrific news."
Durham City MP Roberta Blackman-Woods said: "So upset about what has happened to my lovely, immensely hard working and dedicated colleague Jo Cox. Thoughts very much with her family."