British Transport Police were called to Lewes station on Monday evening (May 29) following reports of a fight on a train.
Two people were taken to hospital with stab wounds.
The incident happened just before 8.30pm on a train that had been traveling from Ore to London Victoria.
A BTP spokesperson said:
"Officers quickly attended alongside paramedics and two victims were taken to hospital for treatment to knife wounds – thankfully neither are life-changing or life-threatening."
"Anyone who witnessed what happened and hasn’t already spoken to police is asked to contact BTP by texting 61016 or calling 0800 40 50 40 quoting reference 594 of 29/05/23.”