Cox, a Labour lawmaker representing Batley and Spen constituency for the House of Commons of the UK Parliament, was shot and stabbed earlier Thursday outside Birstall Library, near Dewsbury, West Yorkshire.
Local police reported they had arrested a 52-year-old man suspected of the attack.
UK Prime Minister David Cameron canceled his rally in Gibraltar campaigning for UK staying in the EU after the assault on Cox.
Cameron said that the death of the lawmaker is a tragedy. A number of UK and EU politicians have also expressed condolences of her death.
The death of Jo Cox is a tragedy. She was a committed and caring MP. My thoughts are with her husband Brendan and her two young children.— David Cameron (@David_Cameron) 16 июня 2016 г.
Deeply saddened by news of the death of Jo Cox— Philip Hammond (@PHammondMP) 16 июня 2016 г.