How to cancel an onBlockRightClick event?

Hey, I want to prevent a player from pushing a button, tuning a note block etc..
I assumed I have to stop the BlockRightClickEvent in onBlockRightClick(), but it doesn't have a "setCancelled()" method or anything. So how to do this then?

 

This also doesn't work :-(

Code:

    @Override
    public void onBlockInteract(BlockInteractEvent event)
    {
        // Is the interacting entity a player?
        if (!(event.getEntity() instanceof Player)) return;
        Player player = (Player)event.getEntity(); // cast...
        if (SpProtect.isAdmin(player)) return; // admin check
        if (event.getBlock().getTypeId() == 25 && plugin.isProtectedArea(event.getBlock())) { // cancel manipulation of note blocks
            event.setCancelled(true);
        }
    }

Any hints?