Alleged Mexican Drug Cartel Thugs Accused of Kidnapping American 'Courier'

— -- A kidnapping and ransom case in the Carolinas suggests just how active Mexican drug cartels have become in the U.S.

Today, authorities identified three purported members of a Mexican drug cartel as the alleged kidnappers of a South Carolina man last week, according to a criminal complaint filed in U.S. District of Court of South Carolina.

The American hostage, who authorities said was drug courier for the cartel, apparently was kidnapped on July 9 and held for ransom, with demands for as much as $400,000 coming from unknown cartel members in Mexico.

After nearly a week in captivity, the hostage was found chained and blindfolded, but alive, in a Roseboro, N.C., home.

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The criminal complaint alleged the kidnapping and ransom demands were triggered by the American courier’s loss of 200 pounds of marijuana. The suspected courier, identified only as "ES" in the criminal complaint, "delivered 200 pounds [$200,000 worth] of marijuana to an unidentified customer. ES 'fronted' the marijuana to the customer, expecting payment at a later date; however the customer absconded with the with the marijuana and never made payment," according to the complaint.

In the days before the kidnapping, the FBI said, the purported cartel operatives demanded repayment for the missing marijuana from ES and his father, “SG” who also was allegedly working as a drug courier.

When the father could not come up with the money, ES was pulled out of his truck at gunpoint the morning of July 9 in St. Matthews, S.C., and went missing, officials said.

The truck was found still running with its doors open in a neighbor’s yard.

Later in the day, ES’ fiance got a call saying that ES had been kidnapped and the caller demanded to talk to SG about a ransom.

Police and federal agents were eventually able to trace the origin of that call to a number in Mexico and soon found that Mexican-based phone had also placed calls to another number in the South Carolina area, officials said. It turned out that local number could be tracked to a man named Juan Manuel Fuentes-Morales, they added.

Fuentes-Morales was allegedly using that phone to communicate with cartel leadership in Mexico, which was making decisions concerning what ransom demands would be made.

The criminal complaint charged that between July 10 and July 15, the hostage-takers placed 13 calls to ES’ fiance and father. The hostage takers "demanded ransom in amounts varying between $100,000 and $400,000," according to the criminal complaint. In addition to the ransom money, according to officials, the kidnappers demanded the return of the “200,” referring to the 200 pounds of marijuana that had disappeared.

Local law enforcement and the FBI were able to listen in on those calls and advised the fiance and father to demand “proof of life” from the kidnappers.

It was the “proof of life” demand that helped break the case and find the hostage. The family asked the kidnappers to provide them with family information that only ES would know.

Law enforcement agents listened in as the caller, allegedly Fuentes-Morales, called his purported bosses in Mexico and told them it would take at least 30 minutes to obtain the information from ES.

Police were able to track the caller's cell phone location as he drove to the home in Roseboro, N.C., where ES was being held, and then listened again as he called the family back with the answer to the "proof of life" question.

Now, law enforcement closed the net. It obtained warrants for the locations in South and North Carolina and, at 5 a.m. Tuesday morning, the FBI’s elite hostage rescue team stormed a home in Roseboro, N.C., where they found ES and arrested Fuentes-Morales and two alleged accomplices, Ruben Ceja-Rangel and Luis Castro Villeda.

The complex, international case ended up drawing a massive law enforcement response.

“The cooperation among federal, local and state law enforcement agencies and across state lines was nothing short of incredible throughout this investigation," David Thomas, the special agent in charge of the FBI’s Columbia, S.C., field office, said in a statement after the arrests. "The attention and resources contributed to this investigation should send a strong message that the FBI and its partners will not tolerate the kidnapping of American citizens."

Extensive resources were sent to the Charlotte and Columbia FBI field offices by FBI headquarters, including the Hostage Rescue Team, a highly trained group of special agents often called upon to respond to an extraordinary crisis. Crisis negotiators, multiple FBI SWAT teams, evidence response teams, analysts, technical specialists and other personnel were also sent to assist.

The suspects made an initial appearance this morning at the federal courthouse in Raleigh, N.C., and will be transferred to South Carolina to stand trial.

The only mystery left in this case was what really happened to that 200 pounds of marijuana: If ES was involved, was he ripped off or did he steal the grass himself? The FBI said the investigation into that aspect of the case was “ongoing.”

ABC News' James Hill contributed to this report.