Gnu screen: kill a frozen tab

try to kill command.

1. select stalled window ( C-a :select <stalled window number> )
2. send kill command ( C-a :kill )

Assuming you are using the OpenSSH client to connect, you can type Enter ~ . to close the connection.

To list the other SSH client escape commands, type Enter ~ ? when connected.

The most simple and direct way, which has always worked for me, is

C-a, k