I've been following this story:
http://www.npr.org/2014/09/14/348351241/estonia-spy-dispute-could-be-russia-making-anti-nato-mischief
I first read about it, a day or two after the incident. It reminded me of stories I was told of incidents in the 1930's when a number of border guards were attacked, taken across the border into Russia, attempting to create some sort of retaliation/provocation. They would either be shot, held for ransom or simply imprisoned.