Armed soldiers are at Sizewell nuclear power stations in Suffolk as part of the security response to Monday’s terrorist bombing in Manchester.

The military presence is part of the Government’s Operation Temperer providing up to 3,800 troops to support police in their security operations, following the attack at Manchester Arena, which left 22 people dead.

A spokesman for EDF Energy, which operates Sizewell, moved to reassure people that the threat level was unchanged on site, where there is always an armed presence. The soldiers are replacing armed officers from the Civil Nuclear Constabulary (CNC), who had been redeployed as part of Operation Temperer.

The CNC said it had provided a number authorised firearms officers to support colleagues in Home Office forces.

“Our civil nuclear sites remain fully protected and the CNC will continue to carry out their core role of protecting nuclear sites and materials, while also being part of the strategic reserve supporting communities across the country,” a spokesman added.

Prime Minister Theresa May announced on Tuesday the terrorism threat was “critical” - the highest alert level - meaning an attack may be imminent. Home Secretary Amber Rudd said 984 military personnel were being deployed in support of the police.

Across Suffolk, people have been told to expect an increased police presence, including armed units, at “key locations and events”.

Chief Constable Gareth Wilson, of Suffolk Constabulary, said earlier today: “There is no specific intelligence relating to Suffolk. However, we continue to ask residents to be vigilant. Policing in the county is under constant review and we are looking at the resources and policing of key events in light of the raised threat level.

“Military personnel are not currently being deployed – but the threat assessment is continuously under review.

“Our thoughts remain with those affected by the tragic incident in Manchester.

In Essex, armed police officers are patrolling major infrastructure sites, with more local policing patrols.

Deputy Chief Constable BJ Harrington, of Essex Police said: “From today and until further notice people in Essex will see an increased police presence in the county and that includes armed police officers. We are doing this to protect and reassure the public and we plan and train in great detail to respond to situations like this.”

People are asked to report any suspicious activity to the anti-terrorist hotline on 0800 789 321 or in an emergency on 999.