People living near a US airbase earmarked to house nuclear weapons say they are being left in the dark about what would happen in the event of a radiation alert.

It comes after a drill simulating an accident involving such material was held, with personnel from RAF Lakenheath in Suffolk taking part.

Nick Timothy, Conservative MP for West Suffolk, said while the US military was “welcome”, there needed to be “transparency as far as possible on issues like this exercise”.

A Ministry of Defence (MoD) spokesman said: “Exercise Diamond Dragon demonstrated our preparedness to respond to any incident, no matter how unlikely”.

The exercise was conducted at nearby RAF Honington.

A US Air Force (USAF) spokesman said: “Airmen from the USAF participated in a small-scale, joint emergency response exercise from September 23-25, 2024.

“The purpose was to train and evaluate combined emergency response procedures in support of military operations and accidents”.

The last exercise was held in 2015, after which a report into what lessons had been learned was published.

The Suffolk Resilience Forum, which leads on emergency planning in the county, confirmed the scenario in both instances was a simulated crash in the UK of a US aircraft carrying “defence nuclear materials”.

Lakenheath Parish Council chairman Gerald Kelly said he had been told informally about the latest drill.

He said the area had an emergency plan, but added: “There is nothing in there about this sort of incident.”

The MoD should inform residents “what it wants us to do” if the event of an incident, he said.

Mr Kelly called for a siren system to be installed and for the local community to be involved in any future exercises.

The Defence Nuclear Organisation, which oversees “all defence nuclear business, excluding operations”, published guidance in 2021 detailing what local authorities should do in case of a nuclear weapons emergency.

One section advised members of the public situated 5km (three miles) downwind of an incident should be evacuated in a 45-degree arc, centred on the wind direction.

Parents would also be advised not to try to collect children from school unless told otherwise.

“The school authorities will look after them,” the document stated.

Lakenheath villagers said they did not know about this advice or Exercise Diamond Dragon.

David Rolph, who has lived locally for 20 years, said: “I think the local people should be well aware of what we can do if something happened on-base and there isn’t any information. There is no noticeboard saying what to do.”

He endorsed the idea of a siren warning system.

Lily Brown, 33, a barber who previously worked at RAF Lakenheath, was not keen on the idea of sirens being installed. “I’d rather not know what’s coming,” she said.

Sally Hunt confirmed she also had received no nuclear safety information, despite living close to Lakenheath for two decades.

“If they are going to have nuclear weapons up there, I think we should be aware of it and know that there are safety measures in place,” she added.

Timothy, who has represented the constituency since last July, said: “We know that exercises like this take place across government, across the military and public services for all sorts of different possibilities all the time.”

A spokesman for the Suffolk Resilience Forum said it would publish a report on the latest exercise.

They added: “This happened in West Suffolk because of the obvious availability and proximity of a suitable location and relevant military personnel.

“This exercise is relevant to anywhere in the UK and does not represent a specific threat to our area.”