After taking on social media platforms last year, Australian authorities are now going after popular online gaming platforms over unsafe content.

The eSafety Commission has issued transparency notices to Roblox, Minecraft, Fortnite and Steam, over concerns they're being used by sexual predators to groom children as well as extremist groups to spread propaganda and radicalise young Australians.

The legally enforceable notice is a 'please explain' to the companies on how they're identifying, preventing and responding to harms with penalties for non-compliance of up to almost $50 million per breach.

• GUEST: eSafety Commissioner Julie Inman Grant
• PRODUCER: Katie McAllister