Experts and U.S. policy makers have reportedly expressed concerns over the possibility of criminals in Venezuela acquiring part of its own military-grade weapons amid civil unrest.

Venezuela decided to arm civilians to defend the country’s socialist government. But the lack of control under Nicholas Maduro’s regime have sparked fears that some of the weapons, including countless modern assault rifles and shoulder-fired surface-to-air missiles, may fall into the hands of terrorists or criminal groups, the Miami Herald reported Monday.

Military documents obtained by el Nuevo Herald show that Venezuela had purchased Russian-made surface-to-air missiles and though militias are only being armed with assault rifles, experts worry that some of the military gear could fall into civilian hands. The U.S. already had concerns with Venezuela having the missiles because of Caracas’ cozy ties with FARC in Colombia and Hezbollah, the Herald reported.

The U.S. was reassured by Russia that the weapons would not fall into the wrong hands, but fears reignited last week when Maduro signed an order to activate militias when facing a possible threat of war while protesters marched in the streets accusing Maduro of attempting a self-coup.

“Maduro is a dictator with close ties to terror-sponsoring regimes, and is now promising a ‘gun for every militiaman’ as his thugs counter the Venezuelan people’s peaceful pro-democracy protests with violence and lethal force,” said Sen. Marco Rubio, R-Fla. “This reckless action reeks of desperation and raises the possibility that Maduro could lose control over dangerous weapons systems.”

A source with knowledge of Venezuela’s military operation told the Herald that given the country’s lack of control, it is nearly certain that the military will lose control over any weapon given to militias. The source said that one militia group may have as many as 5,000 one-man-operated surface-to-air missiles.

“Once they are out, the armed forces will not be able to control them. Any weapon handed out could end up in the hands of Colombian guerrillas, in the hands of drug trafficking groups or they could even end up in the hands of arms traffickers willing to sell them to terrorists,” he said.

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