Conservative MP David Amess has died this afternoon (15) after being stabbed at an event in his local constituency in southeast England.
Police did not name Amess, but said: "A man has been arrested on suspicion of murder after a man was stabbed in Leigh-on-Sea" and that the victim "later died".
Amess was stabbed "multiple times" during an event on Friday in his local constituency in southeast England, Sky News and the BBC reported.
Local police did not name Amess, but confirmed that officers "were called to reports of a stabbing" shortly after 12:05 pm (1105 GMT).
"A man was arrested shortly after & we're not looking for anyone else," the force said on Twitter.
Amess was holding a his regular weekly meeting with constituents at the Belfairs Methodist Church, in the small town of Leigh-on-Sea.
He had advertised the event on his official Twitter account.
There was no immediate comment from prime minister Boris Johnson, who was leading an away-day for senior ministers in the west of England.
But his wife Carrie Johnson said on Twitter, "Absolutely devastating news about Sir David Amess. He was hugely kind and good. An enormous animal lover and a true gent. This is so completely unjust. Thoughts are with his wife and their children."
Health secretary Sajid Javid said, "Devastated to learn of Sir David Amess' murder. A great man, a great friend, and a great MP killed while fulfilling his democratic role. My heart goes out to Julia, his family, and all who loved him.
Let us remember him and what he did with his life."
London mayor Sadiq Khan said, "I am so deeply, deeply saddened by the tragic news that Sir David has passed away. He loved being an MP and was a great public servant. It is just awful. My thoughts and prayers, and those of all Londoners, are with David's loved ones at this time of unimaginable grief."
Former prime minister David Cameron said, "Very alarming and worrying news reports coming from Leigh-on-Sea.
"My thoughts and prayers are with Sir David Amess and his family."
Labour leader Keir Starmer called the news "horrific and deeply shocking".
An eye-witness, identified only as Anthony, told radio station LBC that the scene was "completely and utterly swamped by police, ambulance, armed police.
"I saw someone get taken out the building, put into the back of a police car. Apparently he was stabbed quite a few times."
Other British MPs have been attacked at similar constituency events, including Labour MP Jo Cox, who was murdered in 2016 in the run-up to the Brexit referendum.
Her husband Brendan Cox said, "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 memory, tweeted that it was "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," it added.
Labour MP Stephen Timms was stabbed multiple times during an event in 2010, but recovered from "potentially life-threatening injuries and is still an MP.
Timms said he was "appalled" at the latest attack.
In January 2000, Liberal Democrat MP Nigel Jones was injured and his assistant killed by a man wielding a ceremonial sword at a constituency surgery in Cheltenham. (with AFP)
Bob Blackman MP speaks during the event