A crime crackdown team which started patrolling rail firm Southern's network in April has made 52 arrests so far.
Southern said its Safer Travel Team had also issued 33 cautions, dealt with 14 trespassers, and handed out 1,677 anti-social behaviour warnings.
The team, which responds to incidents and deals with low-level crime, had also given out 516 penalty fares and 245 notices for fare evasion.
It includes British Transport Police and Southern's neighbourhood officers.
The arrests were for possession of drugs, possession of drugs with intent to supply, fare evasion, immigration overstays, and public disorder.
Martin Grier, Southern's head of security and revenue protection, said: "This is a remarkable impact considering the short time the team has been in existence.
"I'm particularly pleased with the number of anti-social behaviour warnings that have been issued."
He said issues such as feet on seats and loud music on trains were just two problems that annoyed passengers intensely and the team was on a mission to stamp out unacceptable behaviour.
Southern provides services between London and the South coast, covering East and West Sussex, Surrey and parts of Kent and Hampshire.