But in any case, they are not buddies, not even colleagues in the same office floor. They at least need to find contacts in the remote country and persuade them

But in any case, they are not buddies, not even colleagues in the same office floor. They at least need to find contacts in the remote country and persuade them to spend time for their task. Sometimes that’s all it takes to prevent them from passively collecting signals, unless you are an important target.