Croatia staged a military parade in Zagreb on August 4 to mark the 20th anniversary of winning its independence from the Serb-led former Yugoslavia.
In Belgrade, Serbia has been mourning those who died in the Croatian military offensive that brought an end to their four-year war.
The parade and other celebrations were being hailed as victory day celebrations in Croatia. About 3,000 soldiers, 300 military vehicles, and 30 military planes took part.
But in neighboring Serbia, August 4 is considered a day of mourning for nearly 700 ethnic Serbs who died in the Croatian "Operation Storm" that crushed the Belgrade-backed ethnic Serb forces in western Croatia in 1995.
Some 200,000 Croatian Serbs fled the offensive. Most have never returned to their homes in and around the town of Knin, the center of the operation.
The anniversary celebrations have burdened relations between Croatia and Serbia for years.
With reporting by AP and dpa