A defiant couple has given voice to the outrage of taxpayers all over the country after standing up to a belligerent teenager caught on video brazenly scratching into a train window in a blatant act of vandalism.

The video, recorded by Melbourne train commuter Kerrie Mason, shows the young long-haired vandal, believed to be in his teens, violently scratching letters into the glass window next to him while travelling on the Lilydale line yesterday.

Despite appearing to know he's being filmed, the young man continues to repeatedly etch into the window, until he confronts the person filming.

View photos The young man continued to scratch despite the couple recording him. Photo: Facebook/Kerrie Mason More

"Do you want to get that out of my f---ing face before I f---ing take it off ya," he snaps, removing his white headphones.

The teens can be heard muttering profanities when fed-up passenger Bryan Coombes intervenes.

"Because this affects other people mate," he yells.

"No it doesn't," the teen replies.

View photos The teen stopped to spit expletives at the couple. Photo: Kerrie Mason More

"People gotta pay for this sh--... have a look at ya, people are over this!"

The vandal doesn't back down, yelling: "Why are you f---ing butting in?"

"Because we're done with it!" the defiant commuter yells loudly.

Bryan continues with an articulate explanation of why the teen vandal's actions affects him personally.

"My money don't go towards this sh-- mate. Not for this crap. It goes towards public transport, it goes towards the system, it goes towards helping everyone get on with their lives.

View photos The vandalism left by the teenager. Photo: Facebook/Kerrie Mason More

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