South Yorkshire residents will see armed patrols on trains for the first time in history in the wake of the Manchester terror attack.
British Transport Police (BTP) have announced that specialist firearms officers will be on trains nationwide from Thursday afternoon as Britain remains on a critical terror level.
BTP said armed officers will be at places where "you wouldn't normally expect them", including at stations or on trains.
The force said the armed officers were there make passengers feel safe and asked them not to be alarmed by their presence.
Deputy Chief Constable Adrian Hanstock said: “Our officers have been given specialist training in counter terrorism policing – including behavioural awareness skills.
"This means that their day-to-day policing role is keenly focussed on keeping passengers and staff as safe as possible.
“Over the coming days, we’ll be keeping a close eye to keep you safe, as well as making sure the nation’s railways keep functioning as usual.
“I want to take this opportunity to remind everyone to stay calm, be vigilant, and if you spot anything at all which gives you cause for concern, let us know.
"In light of the dreadful events over these last few days, and last night’s increase to the national threat level, nothing should be considered too trivial to report and any information – regardless of whether you feel it is significant or not – may be important to all of us.”
Dep Chief Constable Hanstock said their increased does not mean any specific intelligence has been received at any particular station or that there is an increased risk of travelling by train.