Mike Collier in Tallinn -

In a sensational announcement on September 5 at a time when relations between the West and Russia are already tense, Estonia's internal security service, KAPO, said that one of its agents had been abducted from Estonian soil and taken across the border into Russia.

"On September 5th about 9 in the morning the KAPO officer was abducted while on-duty on Estonian territory by unknown individuals who came from Russia. He was captured using force at gunpoint. He was fulfilling his duties preventing cross-border criminal activity. The abductors jammed radio communication and used smoke grenade,” a KAPO statement said, adding that a criminal investigation had started.

According to national broadcaster ERR, the kidnap took place at Luhamaa, in the extreme south-east of the country and close to the borders of both Russia and Latvia.

The strategic location makes it an important one for smugglers, as it is where one of the main road routes to Moscow from the EU passes via the Luhamaa border checkpoint.

While the likelihood is that criminal gangs are responsible for the abduction, the fact that the victim – yet to be named – could be smuggled back across the border will inevitably raise questions about how the kidnappers could get him past Russia's notoriously pernickety border guards and custom officials without some sort of complicity.

KAPO has a reputation about being unusually forthcoming about even potentially embarrassing information such as this. Most famously, KAPO went public in 2009 with information that Herman Simm, a defence ministry senior security official, had been acting as a Russian double agent and it has named other moles after exposing them.

Estonia won widespread praise for the transparency with which Simm's case was treated, which is in stark contrast to how most other security services handle them.

In this case, disclosure is doubly important because in the current testy geopolitical situation border posts are potential flashpoints.

One of the darkest periods in recent Baltic history came when Russian OMON forces attacked Lithuanian border points in 1991, killing eight and injuring more than 60.