Hiding bodies

[Nokturnal]

Yes razputin is correct, you can also drag the hand icon (with right-click) to the line of buttons above the UI for easier access.

Also make sure you have the space in your inventory for a body though, you may have to re-arrange your equipment so you can fit the body in the inventory.
From memory, they are 2sq. high and 4(or 5?) wide, basically takes up a big chunk of your inventory, so don't try picking up bodies with a fully kitted out soldier or you'll have to drop items.