Ticket inspector punched and kicked on train

Image source, British Transport Police

Image caption, Officers believe the four people pictured may have information that could help their investigation

A ticket inspector was punched and kicked after asking a group of people to leave the first-class carriage.

The attack happened just before 13:00 GMT on Monday 20 February as the train was at the platform at Derby railway station.

The group is said to have fled the train and crossed the tracks before jumping a fence towards Pride Park.

British Transport Police said those in the images released might have information that could help their investigation.