NSW Police are concerned gangs are getting their violent and deadly work done by teenagers.

9News can show the weapons that have been seized in a recent crackdown by authorities working to disarm these children.

A musket handgun with a bayonet was allegedly found down the pants of a Western Sydney teenager.

Detective Inspector Guy Magee from NSW Police said it was “extremely alarming”.

“It’s alarming for my staff, alarming for members of the public,” he said.

It’s one of an arsenal’s worth of weapons, most carried by kids before police found them, including knuckle dusters, an axe and knives of just about every shape and size.

One of them was pulled from a boy’s underpants at Bankstown train station.

They’re all part of a police blitz targeting youths and weapons and their worrying link to the underworld war.

In Sydney there have been 12 shootings and almost countless torched cars since Christmas, with two innocent lives lost and another woman shot and left in a coma.

There’s confirmation the troops on the ground, more often than not, are children.

If crime is a business then juveniles really are the near-perfect employees. They’re cheap, eager to impress their bosses, and if they’re caught, they’re often released and back to work quickly.

But what’s more shocking is that to win the attention and contracts of organised criminal networks teen crooks are fighting amongst themselves.

The Mount Druitt Kmart brawl two months ago is an example of this sick game to win favour.

“My message to those who want to be armed in Western Sydney, they need to understand when they do that they are increasing their chances exponentially of ending up in a police cell or a hospital bed,” Magee said.