Make sure he does not escape the tunnel maze and run to hide somewhere else! (petsmagazine.com.sg)
Apart from the Cold war conflict between secret services by building tunnels into enemy territorities, most tunnels were attempted escape tunnels from the GDR into the FRG in Berlin. (politics.stackexchange.com)
Mazurek and Haimi want to continue digging several feet below ground to see how far Sobibór's escape tunnel extends, since they are not sure of its complete length. (scientificamerican.com)