The husband of murdered Batley and Spen MP Jo Cox says the fatal stabbing of another MP "brings everything back."
Sir David Amess was holding a surgery at a church in Essex when he was stabbed several times and killed.
Tributes are being paid to Sir David across the political spectrum.
His death has brought back memories of the last time a serving MP was killed, Batley and Spen MP Jo Cox who was murdered in 2016.
She died in similar circumstances in a shooting and stabbing outside a constituency surgery in Birstall.
Today her husband Brendan Cox has tweeted saying the murder of Sir David Amess "brings everything back."
He tweeted: "My thoughts and love are with David’s family. They are all that matter now. This brings everything back. The pain, the loss, but also how much love the public gave us following the loss of Jo. I hope we can do the same for David now."
The Jo Cox Foundation, which was set up in her name, said it was "horrified" to hear about the stabbing of Conservative MP Sir David Amess.
The foundation tweeted: "The Jo Cox Foundation is horrified to hear the news of the attack on Sir David Amess MP. We are thinking of him, his family and loved ones at this distressing time."
Sir David Amess's death raises more questions about the safety of MPs, coming just five years after the murder of Jo Cox.
The 41-year-old mother-of-two had been the Labour MP for Batley and Spen for just over a year when she was shot and stabbed by Thomas Mair, a social recluse.
She was the first MP to be murdered in office since 1990, when Ian Gow became the last in a string of MPs to die at the hands of Northern Irish terror groups.