It’s been more than 20 years since the Bosnian war ended, but tension is once again rising in the region as Serbia and Croatia begin upgrading their weapon systems.
The Croatian government's plan to buy new weapons systems by next year is raising concerns of a potential arms race in the Balkans.
In a recent military upgrade, Serbia also received six new fighter jets from Russia.
Some analysts say it's a response to Croatia's plans to buy a new arms system from its NATO ally, the United States.
Purchases like these suggest an arms race could be developing in the Balkans.
The current rivalry between Serbia and Croatia dates to the collapse of Yugoslavia in the early 1990s.
Many Serbs are also hostile towards NATO after it bombed their country in 1999 to halt a crackdown on ethnic Albanians in Kosovo during the Kosovo war.
TRT World 's Sally Ayhan has the story from Sarajevo, Bosnia.