Some of the country's top counter terrorism experts are involved in the police investigation into Sir David Amess's death. 

Essex Police Chief Constable Ben-Julian Harrington confirmed the news during a press conference outside Southend Police Station this evening. 

It came after Southend West MP Sir David Amess was stabbed to death while holding a constituency surgery at the Belfairs Methodist Church in Leigh at lunchtime. 

When briefing press on the incident this afternoon, Mr Harrington said: "This was a difficult incident but our officers and paramedics from the East of England Ambulance Service, worked extremely hard to save Sir David.

"Tragically, he died at the scene. A 25-year-old man was arrested immediately at the scene on suspicion of murder.

"He remains in custody.

"A knife was also recovered at the scene.

"The investigation is in the very early stages and is being led by officers from the Metropolitan Police's Specialist Counter Terror Command.

"We made it clear at the time of the incident that we did not believe there was any immediate threat to anyone else in the area.

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"It will be for investigators to determine whether or not this may have been a terrorist incident.

"As always they will keep an open mind."

Mr Harrington also confirmed Sir David had suffered multiple injuries and said officers were on the scene within minutes of the fatal stabbing.

He added: "Today is a tragic day for the family and colleagues of Sir David, the community of Southend and indeed for the whole county.

"Our officers will continue to work around the clock to ensure justice is delivered for Sir David and his family.

"I would like to thank local people here in Southend for their understanding as the investigation continues."

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