A PASSENGER was "sliced open" when a waterside shattered onboard the world's biggest cruise ship.

A section of slide in the Icon of the Seas' waterpark burst just as a young lad was shooting down it, according to eyewitness accounts.

One passenger reported that the kid's "leg and back were cut open pretty bad" by the dangerous malfunction on Thursday.

Footage shows water cascading from the slide onto the deck below.

And a photo taken after the water stopped reveals a jagged hole cut out from one of the panels.

The boy's exact condition is unknown - but it's understood he did not fall through the hole.

He was riding the Frightening Bolt slide, according to Cruise Hive .

This famously boasts the world's highest drop at sea - 46 feet - a dramatic trapdoor launch, and a full 360° loop

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