Croatia and Serbia have moved to ease tensions along their shared border after European Union leaders intervened in a bitter dispute sparked by the migrant crisis.
The two Balkan neighbors in the past week have been locked in their worst spat since the 1990s Yugoslav conflict, imposing tit-for-tat border restrictions after thousands of migrants spilled over their borders in a quest to reach wealthier EU states to the north.
At one point midweek, both sides had effectively sealed their borders, prohibiting goods, trucks, or people from crossing, but they moved to ease the restrictions late on September 25 after a bit of mediation by EU officials.
After receiving a complaint from Serbia about what it called Croatia's "Nazi-era" tactics, the European Commission said it was "urgently seeking clarifications" from Croatia.
Johannes Hahn, the EU's commissioner for European neighborhood policy and enlargement negotiations, said the dispute could be solved only with Croatia reopening its border.
Meanwhile, EU foreign policy chief Federica Mogherini moved to mediate with phone calls to the Serbian and Croatian leaders.
The mediation appeared to work. Croatia's Interior Ministry lifted its border restrictions shortly after hearing from the EU, and Serbia followed suit several hours later.
"Reason has won out," said Serbian Prime Minister Aleksandar Vucic, announcing that all restrictions had been lifted on Serbia's side of the border.
The dispute had led to an escalating war of words and actions and was costing both nations millions of euros in lost trade.
Over the past 10 days, since Hungary sealed its southern border with Serbia, nearly 60,000 refugees and migrants had crossed through Serbia into Croatia, seeking an alternative route toward Western Europe.
Overwhelmed by the sheer numbers, Zagreb closed all but one of its border crossings with Serbia, blaming Belgrade for diverting the flow toward their shared frontier.
Belgrade responded by closing the main Bajakovo-Batrovci crossing -- the last one still open -- to all trucks with Croatian plates, prompting Croatia to close the crossing to trucks and cars with Serbian plates.
Zagreb is now busing most of the new arrivals straight to its border with Hungary, which Budapest has moved to seal.
"The influx of migrants is not going to abate," Hungarian Prime Minister Viktor Orban told reporters in Vienna. "We want to stop people crossing."
After closing off its southern border with Serbia, Hungary this week set up razor-wire fencing along 41 kilometers of its border with Croatia. The remaining 330 kilometers of the Croatian border runs roughly along the Drava River, which is difficult to cross.
Figuring that migrants will now try to start crossing through Slovenia, Budapest this week also began rolling out a mobile barrier along its border with Slovenia, the first such measure within the EU's passport-free Schengen Area.
Hungary backed off efforts to erect razor-wire barriers on the border with Slovenia, however, which would violate Schengen rules.
The influx of refugees has raised tensions not only between Balkan countries but has exposed deep fault lines between Western and former communist Eastern countries in the 28-nation bloc.
There have been growing fears that the Schengen zone could disintegrate as states reintroduce border checks to stem a flow of migrants, many of whom are heading for Germany.
To try to curb the flow of refugees from Syria's four-year civil war, EU leaders earlier this week agreed to boost aid for Turkey, Lebanon, and Jordan, Syrian neighbors which have been hosting millions of the refugees in camps on their borders.