Strange Question (Touch Screen)

Hey everyone,

I have a kind of strange question

I have a touch screen computer and I want to make a little flash game for it.

picture this: the game screen will be like


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now since its touch screen I can tap the screen and that is like a mouse click

current I have it so on a mouse click my hero will move to the mouse click coords.

now I want to add a little box in the bottom left that in NOT clickable because I want a shoot button there and I dont want the char to move there so like this


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How can i make a little box like that which will not detect a mouse click?

lol I hope that all makes sense

Thanks