PODGORICA, Montenegro — Montenegro has started extradition procedures for three men who have been charged by a New York court with conspiring to kill Americans and aid terrorists.

Dejan Djurovic, director of Montenegro's Interpol bureau, said Thursday that "activities for their extradition are underway." They have been labeled by U.S. prosecutors as international arms traffickers.

The men were arrested this week in Montenegro. U.S. authorities say they were unaware they were dealing with U.S. Drug Enforcement Administration confidential sources.

U.S. prosecutors say Cristian Vintila and Massimo Romagnoli of Italy and Romanian Virgil Flaviu Georgescu conspired to sell large quantities of military-grade weapons to the Revolutionary Armed Forces of Colombia, known as FARC. They could face life in prison, if convicted in the United States.