Survival specialist Bear Grylls has taken to Twitter to blast critics who have called his Channel 4 show fake.

Channel 4 was accused of fakery after it emerged producers set up a water supply and let loose two crocodiles on the survival show, The Island with Bear Grylls.

It had also emerged that four of the “13 ordinary men” marooned for a month were TV professionals with experience of extreme conditions and at least two had worked with Bear before.

Bear has broken his silence to speak about the set-up of the show while challenging critics to have a go themselves.

The Mirror newspaper reports that the TV star posted: “I don’t understand the critics here – yes production made sure the 13 men wouldn’t die & @TheIsland had a source of water & food.”

He continued in a series of posts asking people not to “belittle the men’s courage and resolve”.

Bear then thanked those who posted that it was a good show and retweeted messages backing his argument.

The Island with Bear Grylls, C4, Monday, May 19.