Federal prosecutors in Minnesota announced charges Friday against three men accused of conspiring to illegally export drone aircraft technology to a terrorist organization in Lebanon.

An indictment unsealed Friday detailed a complex international scheme through which the men sourced drone materials from businesses around the world — including digital compasses made by Honeywell in Minnesota — for members of the Hezbollah terrorist group.

Interpol agents arrested Usama Darwich Hamade, 53, and his brother Issam Darwich Hamade, 55, in South Africa this week while a third co-conspirator — Samir Ahmed Berro, 64 — is still at large, authorities said. The three are accused of evading international export controls to funnel parts including drone technology, a jet engine, piston engines and "recording binoculars" to Hezbollah members from 2009 to 2013.

"This indictment describes an elaborate conspiracy and scheme to allegedly provide goods and technology to Hezbollah," U.S. Attorney Gregory Brooker said in a statement. "The investigation of this case was extremely complicated and our federal law enforcement partners at the FBI, the U.S. Department of Commerce's Office of Export Enforcement, and Homeland Security Investigations conducted a thorough investigation and we are thankful for their dedication."

Usama Hamade, aka "Prince Sam," holds both Lebanese and South African citizenship. His brother, Issam Hamade, is a citizen of Lebanon who had been living in South Africa at the time of his arrest. According to the indictment, Berro, aka "Tony," was thought to have been living in either Jordan or Lebanon during the conspiracy and holds citizenship in both Lebanon and the United Kingdom.

Berro owned an engineering firm called SAB Aerospace in Dubai, according to the charges, allegedly used as a transshipment point for piston engines shipped from the U.S. to Germany and eventually destined for Hezbollah.

The indictment cited two unnamed people in South Africa and Arizona, respectively, who aided the conspiracy but either did so unwittingly or "did not fully understand the scheme's illegal purpose." In some cases, the charges said, Usama Hamade allegedly lied about the intended use of certain products he "directed" the unidentified South African to order and deliver to Berro's business.

For example, Hamade told the person, called "Individual A" in the indictment, that drone parts scheduled for delivery in South Africa would be used to fly over wildlife areas on anti-poaching missions.

Instead, the parts were "transshipped" from South Africa to Hezbollah members after making stops in states like Minnesota along the way as part of an illicit, and elaborate, supply chain.

Followers or 'useful idiots'?

According to charges, Issam Hamade also allegedly made nearly $174,000 in wire transfers from a bank in Beirut to accounts his brother controlled in Lebanon to pay for the drone parts, describing the payments as "family support" or funds for "his brothers" to buy "spare parts."

The United States is seeking to extradite the Hamade brothers, according to court filings, and a court hearing in South Africa is expected to take place next week.

An ally of Iran and Syria, Hezbollah is considered a terrorist organization by both the United States and the European Union. The group supported insurgents who engaged U.S. troops in Iraq and has increasingly relied on international supporters for weapons and drone procurement as it stepped up its role in the Syrian civil war.

Matthew Levitt, director of the Washington Institute's Stein Program on Counterterrorism and Intelligence, said the new charges out of Minnesota "demonstrate that Hezbollah has a sophisticated illicit procurement program that's proactively engaged around the world" — including the U.S.

It's unclear whether the three men indicted are merely supporters using their professional expertise to help the group or if they have deeper ties to Hezbollah. Levitt said the FBI has described some like-minded followers as "useful idiots," but others may be actual members with a talent for money laundering or other skills put to illicit use.

"It is indicative of the fact that Hezbollah is deeply involved in these types of activities at multiple levels involving multiple groups, individuals, and … using different companies at the same time," Levitt said.