From this afternoon, firearms officers will be deployed to patrol trains across the country.

British Transport Police said it was a measure to make sure people were kept safe.

Armed officers have been regularly patrolling on the London Underground since December, but this will be the first time they will patrol on board train services elsewhere in the country.

A spokesman said: " Passengers should not be alarmed by their presence and know that officers are there to disrupt and deter criminal activity."

Chief Constable Paul Crowther said: "Since the devastating events in Manchester on Monday evening, our force has radically increased the presence of our officers nationwide.

“By having firearms officers on board trains we’re ensuring that trains remain as safe as possible for passengers.

Our patrols will be highly visible and passengers should feel comforted by their presence. Please do speak to them if you have any concerns at all.

“This is part of our national mobilisation plan to deal with the current and ongoing threat.

"It is important to note that we do not have any specific intelligence in relation to train services but are taking this action to ensure we can protect and reassure the public.”