When they are in the forest they are there illegally. they go at night so they won't be seen but then use torches and talk in rather loud voices. This defeats the object of going at night.
The fence has a huge hole in it which would not happen as these bases have patrols checking for breaches and/or intruders around the perimeter.
They appear to be very very scared but they still hang on to their metal detectors. Anyone else, as scared as they are would have dropped it and ran as fast as possible.