Lithuania's new visa requirements for Russian citizens traveling between the mainland and Kaliningrad have taken effect as part of Lithuania's preparations to join the European Union. But the first day of travel under the new procedures was not without incident.

Close to 50 Russians were reportedly thrown off transit trains in the first day of the new visa rules for Russian citizens traveling between the mainland and the Baltic enclave of Kaliningrad.

The commander of the Lithuanian border guards service blamed Russian authorities for the confusion, saying they let passengers without the new transit documents board the trains.

According to the commander, the vast majority of passengers on trains from Moscow followed the rules. But he says trains arriving from other Russian cities are creating numerous problems.

The new regulations have been a bone of contention with Moscow, but an official with Russia's railway ministry acknowledged that there is still some confusion about the process, and agreed Russia was at fault. The transport official said the Russians removed from the train will be allowed to travel onward, but not for at least another day.

When Poland and Lithuania join the European Union next year, Kaliningrad will be totally surrounded by EU countries and the issue has been a sensitive topic in EU-Russia relations.

Under a hard-fought deal last November, the European Union and Russia agreed travelers would be issued essentially a low-cost, multiple entry visa for roughly six dollars. There is no cost to travelers wanting to make the trip just once.

As the new regime came into force, Russia's special representative for Kaliningrad boarded a train to check out the experience first-hand. He noted that traffic was light and predicted it could stay that way for a while, as travelers hold out to see how the new arrangement will work.

Meanwhile, the Russian air carrier, Aeroflot, has increased daily flights to the enclave to offset potential train travel problems. Aeroflot officials say that unlike the trains, the plane is packed, with tickets selling out days in advance of the new visa rules going into effect.