How can I block a specific wireless network using the terminal [duplicate]

I am trying to block a specific Wireless Network such as "Router_Home" because everytime I wake up my laptop the first thing that the Network Manager does is to try connecting to this Network.

Can you show me how to do that using the terminal or/and GUI ?

EDIT: I know I can uncheck the "connect automatically" option. But I want to know how to block a wireless network totally.

I am using Ubuntu 12.10

If I understand you correctly, you can just delete the connection from network manager by going to the network manager -->edit-->wireless then highlight the connection and click delete.

There is also a package in the repos called nmcli that is a command line interface for network manager, but I haven't tried it.