Federal officials in the U.S. state of Arizona have indicted 13 Bosnian Serbs on charges of lying on their visa applications about their prior military service.

Officials said seven others were being held on similar charges.

The indicted ethnic Serbs from Bosnia-Herzegovina are charged with concealing their prior service in Bosnian Serb forces. However, some families of the accused have said they did not serve in the military; others said they were conscripted against their will.

Last year, four other Bosnian Serbs in Arizona were arrested and charged with lying on immigration paperwork.

All immigrants applying for legal residency in the United States must disclose prior military service.

Widespread atrocities occurred during the conflict of the 1990's in Bosnia-Herzegovina, including the slaughter of thousands of civilians by Serb forces.

Some information for this report provided by AFP and AP.