A Conservative MP has died after been stabbed in an attack at his constituency surgery.
Sir David Amess, the MP for Southend West in Essex, suffered multiple injuries on Friday at Belfairs Methodist Church in Leigh-on-Sea.
Essex Police said a man had died, and a suspect was arrested on suspicion of murder.
Counter-terror police are involved in the early investigation into the stabbing and are working to establish the potential motivation.
There has not yet been any confirmation of whether the incident is being considered terror-related.
Police were called to the scene shortly after noon on Friday and said the surrounding roads have been closed off.
A spokesperson for Essex Police said: “We were called to an address in Eastwood Road North shortly after 12.05pm today.
“We attended and found a man injured. He was treated by emergency services but, sadly, died at the scene.
“A 25 year-old man was quickly arrested after officers arrived at the scene on suspicion of murder and a knife was recovered.”
Police said the suspect was being held in custody, and that they were not looking for anyone else in connection with the incident.
One witness called the incident “very distressing” and described seeing someone being taken out of the church and put into the back of a police car, before he was asked to leave the area.
“At that point obviously we knew something serious had happened,” he told LBC radio.
“Within five minutes we'd been informed by someone who was actually in the building what had happened and apparently he (Sir David ) had been stabbed quite a few times. It's very distressing.”
Sir David had advertised the surgery, which is a regular opportunity for constituents to air their views and seek assistance, on his Twitter page on Tuesday, giving the location and contact details to book an appointment.
Pictures taken of the scene of the incident showed a police car and multiple ambulances parked on the road, with the area cordoned off to the public.
Brendan Cox, the widower of murdered Labour MP Jo Cox, wrote on Twitter: “Attacking our elected representatives is an attack on democracy itself. There is no excuse, no justification. It is as cowardly as it gets.”
Politicians reacted to the news on Friday, with Labour leader Keir Starmer saying: “Horrific and deeply shocking news.”
Former prime minister David Cameron tweeted: “My thoughts and prayers are with Sir David Amess and his family.”
Conservative MP and former party leader Sir Iain Duncan Smith said he had been praying for a full recovery “following this appalling, shocking news”.
He added: “This angry, violent behaviour cannot be tolerated in politics or any other walk of life.”
Sir David was first elected to parliament to represent Basildon in 1983, and then stood for election in Southend West in 1997.
He is the current chair of the All-Party Parliamentary British-Qatar Group, and recently met the country's emir in Doha.
On his website, he lists his main interests as “animal welfare and pro-life issues”. Sir David has a wife and five children.
Essex Police said anyone with information should contact the force quoting incident 445 of 15 October.
Additional reporting by PA
