Luis Antonio "Flaco" Ramirez allegedly organized a complex caravan system through private ranches in Starr, Zapata and Jim Hogg counties

Luis Antonio "Flaco" Ramirez, 20, of Roma, allegedly organized a complex caravan system through private ranches in Starr, Zapata and Jim Hogg counties to avoid detection at U.S. Border Patrol checkpoints.Once north of the Rio Grande Valley, Ramirez's workers cut across Central Texas before delivering their loads to Houston. One worker told authorities each load carried at least a half-ton of narcotics and sometimes much more, according to a criminal complaint filed in Ramirez's case.Over the past two years, agents seized eight loads believed linked to his organization in traffic stops, raids on stash houses and one incident at a Laredo hotel. In all, they found 9 tons of marijuana and more than 4 pounds of cocaine in locations between Laredo and Houston.In one series of stops, the Goliad County Sheriff's Office attempted to pull over a Ford Expedition on suspicion of a traffic violation. But as deputies stepped out of their car, a pickup truck sped toward them and almost struck an officer. The authorities aborted their stop on the Expedition and instead pursued the truck.Later that day, police in El Campo - a small city between Houston and Victoria - tried to pull over the same Expedition, but a GMC Denali allegedly driven by Ramirez was used to try to prevent the officer from doing so.Cooperating witnesses said such tactics were typical of Ramirez's smuggling operation, according to the complaint.Each vehicle carrying a drug load was accompanied by four other cars - a scout up front, two vehicles in the back and another car driven by Ramirez, the witness said. If the load vehicle encountered any problems with authorities, one of the accompanying vehicles would try to create a distraction.The group got through private ranches by bribing gatekeepers up to $2,500, the document states.Ramirez was arrested Feb. 19 on unrelated warrants for evading and resisting arrest in Starr County. He later confessed his involvement in the drug conspiracy to federal investigators, according to court documents.He remains in the custody of U.S. Marshals on drug trafficking and conspiracy charges. It was not immediately clear Wednesday whether he had hired an attorney.More than 10 of his alleged accomplices also face various state and federal charges in connection with the group.