COPPER wire thieves have played havoc with V/Line services on the North East railway this week.
They struck on Tuesday and Friday, swiping the wire from the signals between Melbourne and Seymour.
The thefts sparked delays to Albury runs on Tuesday and Friday.
The removal of copper wire stops the signalling system from operating as normal and means trains run at slower speeds until repairs can be done.
"Acts of vandalism including copper wire theft don't just delay trains, they are extremely dangerous and will not be tolerated," a V/Line spokesman said.
"We thank passengers for their patience when travelling on services which were delayed due to copper wire theft this week."
Police are investigating the thefts.