An area of north-west Suffolk largely reliant on the custom of those occupying the US military bases at its heart - RAF Lakenheath, Mildenhall and Feltwell - is often known as "Little America".

In the past seven decades, tens of thousands of US military personnel, their spouses and their children have set up home in this Suffolk enclave for postings lasting between two and four years.

There is no defined border for "Little America" - arriving there is mostly signalled by a preponderance of large, American cars and signs bearing the Stars and Stripes.

Many businesses in the area also accept payment in dollars.

At RAF Lakenheath there are about 5,500 active-duty military members and 2,700 British and US civilians working on base

The United States Air Force claims RAF Lakenheath and Mildenhall are worth a combined £700m ($910m) to the local economy.

Laurence Cawley
BBC News

Days like today are the ones everybody at RAF Lakenheath fears the most.

Six years ago an F15 went into a tail spin before crashing into the ground close to homes in Western Hills, Lincolnshire. The base commander at the time told me how his primary fears were the safety of UK citizens, the safety of his air crew and the USAF’s relationship with its host country.

Many would be surprised at just how unlike USAF pilots are to the characters portrayed in films like Top Gun.

The changing rooms before a training mission are intensely serious places, with pilots quietly ruminating on every last detail of the flight ahead.

A short walk from the changing area is a room called "the vault".

"The vault holds all the classified information those with clearance need to piece together exactly what happened during a particular flight or mission,” the then commander told me.

That's where all of the voice, sensor data and display recordings will be. It will be from this same vault that the exact cause of today’s crash will emerge.

In a video posted on Twitter, Col Will Marshall, from the 48th Fighter Wing at RAF Lakenheath, said that the pilot was still missing but he was "hopeful" he will be found.

RAF Lakenheath's 48th fighter wing say that the pilot of the jet is "still missing" after the F-15 they were flying crashed in the North Sea at about 09:40 BST.

• A US F-15 fighter jet crashed in the North Sea at about 09:40 BST
• There was one pilot on board, but their status remains unknown
• A search and rescue mission is under way at the site of the crash, 74 nautical miles (137km) off the coast of East Yorkshire
• The flight originated from RAF Lakenheath in Suffolk - a US air base
• The crashed jet had been one of four flying in a formation as part of a "routine training mission"

Pictures from the Yorkshire coast show fog over the North Sea after a US fighter jet crashed.

• CNN report , externalthat the crashed jet was part of a US Air Force mission
• The New York Post, external writes that RAF Lakenheath is home to the United States' only F-15 fighter wing in Europe
• ABC News, external says the air craft was a F-15C Eagle

Data from MarineTraffic - a website that tracks ships and vessels using GPS - shows that an RNLI lifeboat is on its way to the scene of the crashed US fighter jet.

The search and rescue crew from Scarborough were deployed at 09:20, according to data on the website.

Image source, MarineTraffic

It is reported that the US fighter jet has crashed off the coast of East Yorkshire.

It had been in a formation with three other jets, but for reasons as yet unknown, crashed into the North Sea at 09:40 BST.

The jets, from RAF Lakenheath, were on a "routine training mission".

On Twitter, the aviation acccount @CivMilAir shares an indication of the effort going into the search and rescue operation.

In a post at just after 11:00 BST, they said military aircraft were circling the crash site with search and rescue teams deployed.

• A US fighter jet has crashed into the North Sea
• One pilot was aboard - their status is unknown at this time
• The F-15 was 74 nautical miles (137km) off the coast of East Yorkshire at the time of the crash
• The flight had originated from RAF Lakenheath in Suffolk - a US air base
• The crashed jet had been flying in a formation with three other jets when it crashed at 09:40 BST
• A search and rescue operation is under way with support from HM Coastguard

Royal Air Force Lakenheath is a military base that is run and operated by the US Air Force.

Lakenheath had been solely used by the RAF during the 1939-45 conflict and was abandoned as an operational base at the end of the war.

The United States Air Force's 48th Bombardment Group, the forerunner of the 48th Fighter Wing, was relocated from Chaumaunt, France, to RAF Lakenheath in 1960 when the USAF took over the base.

It is home to thousands of US service men and women who are stationed there throughout the year.

Search and Rescue teams are looking for the crashed US fighter jet, which is believed to have crashed 74 nautical miles (137km) off the East Yorkshire coast.

A spokeswoman for HM Coastguard said: "The HM Coastguard helicopter from Humberside has been sent along with Bridlington and Scarborough RNLI lifeboats.

"Following a Mayday broadcast by HM Coastguard, other vessels nearby are heading to the area."

RAF Lakenheath's 48th fighter wing has tweeted, confirming news of the crash.

They say that a search and rescue effort is under way to find the pilot who was aboard the jet, which crashed into the North Sea at 09:40 BST.

The BBC's defence correspondent Jonathan Beale reports that the crashed fighter plane was one of four US jets flying in a formation when it crashed at 09:40 BST.

RAF Lakenheath say that the crashed fighter jet had been on a "routine training mission" at the time it was lost in the North Sea.

It is not yet known what caused the US Air Force F-15C Eagle aircraft to crash.

The crashed jet was a US Air Force F-15 fighter jet.

The aircraft was from the 48th fighter wing at RAF Lakenheath - an air base in Suffolk.

One pilot was on board when the jet crashed into the North Sea at 09:40 BST. Their status is reported as "unknown" and a search and rescue operation is under way.

A US Air Force pilot is missing after a fighter jet from RAF Lakenheath in Suffolk crashed into the North Sea.

We will bring you live updates on this story as it develops.