We have been known to tell kid's (and some others) that their room looks like a bomb has gone off, but this is scary.  

"The bomb squad has been called to a home in far north Queensland after a mother found a hand grenade in her child's bedroom."

Apparently the boy found it in a park.

http://www.abc.net.au/news/2015-07-08/mother-finds-inert-hand-grenade-in-childs-bedroom-cairns/66027...