SARAJEVO (Reuters) - Police in Bosnia, Croatia and Slovenia arrested 13 people on Monday on suspicion of identity theft, seizing weapons and forged documents in a crackdown on Balkan criminal gangs.

Bosnian authorities said eight people including a police official were arrested in the Bosnian towns of Banja Luka, Gradiska and Sanski Most, while three others were detained in Croatia and two more in Slovenia.

"During the raids in each country, police seized weapons, a large number of forged documents, mobile phones, SIM cards and computer and photo equipment," the Bosnian Serb Interior Ministry said in a statement.

Bosnia's security agencies have stepped up cooperation with their neighbors in their fight against organized crime as part of the country's drive to become a member of the European Union.

The suspects were believed to have made thousands of euros by using stolen personal data of Bosnians living abroad to create forged identity cards and biometric passports, which were sold to organized crime gangs in Serbia, Croatia, Montenegro, Slovenia and Bulgaria, Bosnian authorities said.

Serious organized crime emerged during the Balkan wars in the 1990s as Yugoslavia fell apart, spawning sophisticated networks that exploited poorly policed borders, a glut of cheap firearms and a political and security establishment riddled with corruption.

(Reporting by Maja Zuvela; editing by Giles Elgood and Dominic Evans)