It turns out that the Mexican cartel may be way more active in the U.S. than previously thought. 

Just last week, three alleged members of a Mexican cartel are suspected of kidnapping a man in South Carolina, according to a criminal complaint filed in U.S. District of Court of South Carolina.

According to the complaint, the American hostage is an American drug courier for the cartel who was kidnapped after not remitting payment for a massive amount of marijuana.

The man, identified only by the initials ES, "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.

After not making good on the payment for the weed, ES was kidnapped by the cartel members on July 9 and held for ransom, with cartel members in Mexico demanding about $400,000 in ransom for his safe return.

According to the FBI, the kidnappers demanded repayment for the missing marijuana from not only ES, but his father, “SG."

Authorities have allegedly identified SG as a drug courier for the cartel as well.

When neither the father or his son came up with the demands for money, cartel members kidnapped ES at gunpoint and went missing.

He was found nearly a week later in a house in Roseboro, N.C., where he had been chained and blindfolded.

Ultimately, authorities were able to trace phone calls to ES' fiance to a number in Mexico, and followed the trail to South Carolina, according to officials.

It was through that series of calls that authorities identified one man, Juan Manuel Fuentes-Morales, who was communicating with the cartel in Mexico about the kidnapping.

According to the complaint, cartel members contacted the family of ES about 13 times between July 10 and July 15, demanding ransom in amounts varying between $100,000 and $400,000, as well as the return of the 200 pounds of marijuana.

The police pinpointed two more alleged kidnappers through these ransom calls, Ruben Ceja-Rangel and Luis Castro Villeda. The three men were arrested and charged with the kidnapping of ES. 

Authorities have not released information on the nationalities or cartel the men are associated with.