ABC

Public transport authorities are reassuring racing fans the system can cope with crowds heading to Flemington for the Melbourne Cup on Tuesday.

Extra public transport officers will patrol the line to Flemington.

Thousands of train passengers were stranded at the racecourse last year on Oaks Day when train services were down because of a power blackout.

Metlink chief executive Bernie Carolan says the rail system is ready for Derby Day tomorrow and Tuesday's Cup Day.

"Every preparation on the train service has been taken that can possibly be taken," he said.

"We're very confident that people needn't worry about that.

"People want to relax and go to the Spring Carnival ready to enjoy themselves and that's exactly what they should do."

Earlier this week, police warned racegoers about sophisticated teams of pick-pockets targeting people at the Spring Racing Carnival.

They think crime syndicates from Eastern Europe and South America are behind the thefts.

Sergeant Mark Vonarx says authorised transport officers have been asked to detain people they suspect are involved.

"We have asked them to effect what we describe as a citizens' arrest," he said.

"Any person can effect the arrest, and in a situation where they actually witness an offence taking place, they can apprehend and hold the person responsible until police arrive."