Viking FM presenter Alex Duffy is going to want to watch his back after this prank.

The British radio presenter had co-host Emma Louise Jones fearing for her job and more after he convinced her they were on the air and proceeded to read out a list of the top ten most offensive words.

Powerless to intervene, Jones just has to grin/scream and bear it and her reaction is priceless.

Emma thought we were live on-air... We weren't. Let's see how mad she got when I threw in some naughty words.

Posted by Alex Duffy at Breakfast - Viking FM on Thursday, March 3, 2016

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