Plainclothes police officers will be carrying guns around Lancashire today - this is why

That's because the casually dressed men and women armed with firearms are in fact plainclothes police officers taking part in a training exercise.

Lancashire Police said the armed officers will only be identifiable by their baseball caps which will have the word 'POLICE' on them.

It has taken to social media to alert the public to the potentially alarming site of the armed officers, who will be taking part in dramatic staged scenes across the county today.

The force said the armed officers will begin their training exercise in Preston, but could "end up anywhere" across the north and west of the county, "depending on traffic".

Lancashire Police said it could not comment on what type of 'real-world' scenario the officers would be training, but said the operation is a 'routine exercise'.

A police spokesman said: "We'll have some firearms officers out and about across the county today carrying out a training exercise

"Officers involved will be in plain clothes but will be identifiable as they'll be wearing police caps.

"The exercise is nothing to worry about and is simply part of their ongoing training.

"The training will start in Preston, but the officers involved could end up anywhere across the west and north of the county depending on traffic."

It said the armed officers will only be identifiable by their baseball caps, versions of which can worryingly be bought by anyone for less than £5 from online retailers.

In a bid to reassure the public, the force has encouraged people to "feel free to give them a wave if you see them!"

It goes without saying that if you see men and women in casual clothes carrying guns who are not wearing a 'police' baseball cap, you should still call 999.