All rail lines have reopened between Lewes and Seaford after police dealt with an incident this evening, according to Southern Rail.
In a post on social media, Southern said police attended reports of 'passengers causing a disturbance on a train'.
It wrote: "Following passengers causing a disturbance on a train between Lewes and Seaford, all lines have now reopened.
"Services may be subject to cancellation and delay."
It comes after Southern said police were dealing with an incident, which blocked all lines between the stations.