The maritime union has warned of possible industrial warfare in Fremantle as stickers emerge that make threats against scab labour, using the image of a shotgun.

Fremantle Ports hit back, saying any worker caught putting up “intimidating” stickers would be disciplined or sacked.

Posted anonymously around the port this week, the stickers are aimed at scab labour and feature a cartoon with a double-barrelled shotgun held by a maritime unionist.

The stickers, produced by the Maritime Union of Australia, include the logo: “When you scratch a scab . . . it bleeds.”

Union secretary Chris Cain said yesterday he was not familiar with the stickers but said they did not sound threatening, claiming other unions used equally bold logos.

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