Tributes are pouring in for Labour MP Jo Cox after she was killed by a man wielding a gun and knife. She was shot and repeatedly stabbed in her own constituency near Leeds and was pronounced dead just over 48 minutes later by a doctor working with a paramedic crew trying to save her life.

The Union flag is flying at half-mast over the Houses of Parliament, Downing Street and Buckingham Palace, while in Birstall hundreds of people attended a vigil at a local church. Many people, some weeping, laid flowers outside the Houses of Parliament.

Jo Cox tributes
A message is seen on a floral tribute left near the scene of the murder of Labour Member of Parliament Jo Cox in BirstallPhil Noble/Reuters
Jo Cox tributes
A woman wipes away a tear as she looks at tributes left for Jo Cox in Parliament SquareStefan Wermuth/Reuters
Jo Cox tributes
Messages from well-wishers are seen on a board in Parliament SquareStefan Wermuth/Reuters
Jo Cox tributes
Tributes to Labour Party MP Jo Cox are placed on her houseboat in Wapping, LondonNeil Hall/Reuters
Jo Cox tributes
People sign messages of condolence for Jo Cox during a vigil in Parliament Square, LondonDan Kitwood/Getty Images

Her husband Brendan said: "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."

Colleagues expressed their shock and disbelief at the death of Cox, a Cambridge University graduate who had spent a decade working for aid agency Oxfam and was known for her work on women's issues. "We've lost a wonderful woman, we've lost a wonderful member of parliament, but our democracy will go on," Labour leader Jeremy Corbyn said in a televised statement. "As we mourn her memory, we'll work in her memory to achieve that better world she spent her life trying to achieve."

Prime Minister David Cameron said the killing of Cox was a tragedy. "We have lost a great star," said Cameron. "She was a great campaigning MP with huge compassion, with a big heart. It is dreadful, dreadful news."

Jo Cox tributes
Labour leader Jeremy Corbyn attends a vigil for Jo Cox in Parliament SquareDaniel Leal-Olivas/AFP
Jo Cox tributes
Labour MP Yvette Cooper hugs the vicar at St Peter's Church after a vigil in memory of Jo CoxPhil Noble/Reuters
Jo Cox tributes
Labour MPs Yvette Cooper and Rachel Reeves leave St Peters church in Birstall after attending a vigil for Jo CoxOli Scarff/AFP
Jo Cox tributes
Imam Saeed Makda speaks with the vicar after attending a vigil at St Peters church in BirstallOli Scarff/AFP
Jo Cox tributes
A woman leaves a floral tribute next to a photograph of murdered Labour Member of Parliament Jo Cox in Parliament Square, LondonStefan Wermuth/Reuters
Jo Cox tributes
A message is seen on a floral tribute left near the scene of the murderPhil Noble/Reuters
Jo Cox tributes
A young girl leaves flowers in Market Square, BirstallChristopher Furlong/Getty Images
Jo Cox tributes
A man prepares to lay a bunch of flowers near the scene were Jo Cox was killedOli Scarff/AFP
Jo Cox tributes
A card in tribute to Jo Cox is seen near the scene where she was killed in BirstallPhil Noble/Reuters
Jo Cox tributes
People place floral tributes and candles at Parliament SquareDaniel Leal-Olivas/AFP
Jo Cox tributes
A book of condolence is seen near Jo Cox's houseboat in WappingNeil Hall/Reuters
Jo Cox tributes
A woman and child leave a floral tribute for the murdered Labour MP in Parliament SquareStefan Wermuth/Reuters
Jo Cox tributes
Floral tributes and messages are left in Market Square in Birstall, in memory of Jo CoxChristopher Furlong/Getty Images
Jo Cox tributes
A message is seen on a floral tribute left near the scene of the murderPhil Noble/Reuters
Jo Cox tributes
Flowers and tributes are left in Market Square, BirstallChristopher Furlong/Getty Images
Jo Cox tributes
Roses for a Yorkshire rose are placed at the base of a statue of Joseph Priestley in BirstallOli Scarff/AFP
Jo Cox tributes
A police officer carries bunches of flowers at the scene of the murder of Labour MP Jo Cox in BirstallPhil Noble/Reuters
Jo Cox tributes
A message is seen on a floral tribute laid at Market Square in BirstallChristopher Furlong/Getty Images
Jo Cox tributes
Flowers are laid at a statue of Joseph Priestly in Birstall, near the scene where Jo Cox was killedOli Scarff/AFP
Jo Cox tributes
Lucy Powell MP for Manchester Central wipes away tears as she pays her respects near the scene of the murderPhil Noble/Reuters
Jo Cox tributes
A message is seen on a bunch of flowers left at Parliament SquareDan Kitwood/Getty Images
Jo Cox tributes
Women leave tributes near the scene of the murderPhil Noble/Reuters
Jo Cox tributes
Tributes are left to Jo Cox on Parliament SquareDan Kitwood/Getty Images
Jo Cox tributes
A young woman becomes emotional as she arrives to leave a floral tribute near the scene of the murderPhil Noble/Reuters
Jo Cox tributes
A note of condolence is pictured at Parliament SquareDan Kitwood/Getty Images
Jo Cox tributes
Flowers surround a picture of Jo Cox during a vigil in Parliament SquareDan Kitwood/Getty Images

Jo Cox fought against poverty and discrimination in developing countries, worked in Parliament for a solution to the civil war in Syria and campaigned for Britain to remain in the European Union. In charity work and politics, she took up causes across the globe, from some of the world's most dangerous countries to her home constituency in Yorkshire.