The curious thing is that the intruder climbed the undefended section. Coincidence? Or not?
If I read the story correctly, the sensors were removed when the fence height was raised. Again, when?
My question is why didn’t they have the new sensors on hand when they raised the fence and removed the old??????
Why were they removed, when were they removed and were they supposed to be replaced.
Until we know those answers it is all speculation