The inauguration of a new libertarian mini-state in the war-ravaged Balkans may sound like an elaborate joke. But Croatian and Serbian authorities aren't laughing.

The so-called Free Republic of Liberland, a 7-square-kilometer (3 sq. mile) patch of swampland on the banks of the Danube, between Serbia and Croatia, has been blocked for over a week by police in both states.

The heavily forested area where deer and wild boar roam has been claimed by a group of Czech, Swiss, Danish and others who have announced they are forming of a tax haven — like Monaco or Liechtenstein — in the heart of the Balkans.

Things aren't going that smoothly for the new "nation," where self-declared President Vit Jedlicka planned to start inhabiting the land this week.

Croatia deployed border police units and patrol boats to prevent repeated attempts by dozens of Liberland organizers and their followers to reach the uninhabited area, whose only building is a run-down abandoned hunter lodge. Serbian police prevented them from crossing the border from their side.

"The police did their job maybe even better than expected," said Jedlicka, a member of a small libertarian Czech party. "Even the people who wanted to give us the boats were searched and were told that they are not allowed to give us the boats.

"But we won't give up that easy," he said. "We'll keep on trying."

Jedlicka in April planted Liberland's yellow-and-black flag on muddy land a little bigger than The Vatican. He says that the particular area was chosen because it is a rare "unclaimed" territory in Europe. The truth is that both Serbia and Croatia claim that land and still need to settle their border dispute stemming from the 1990s Balkan wars.

Legal experts in both Serbia and Croatia say that the territory is not a no-man's land, and that Jedlicka has no legal right under international law to claim it.

"It is legally senseless that someone sticks a flag on a disputed territory and declares it an independent state," said Bojan Milisavljevic, a law professor at Belgrade University....