McAllen — The short, baby-faced man had no choice, he told the judge during a recent detention hearing. Either he moved the drugs for the Gulf Cartel, or his captive brother would be tortured and killed.

Wearing a white t-shirt, blue jeans and a poorly concealed expression of fear, 21-year-old Isaac Sanchez Gutierrez of Mission bore little resemblance to the man described in court records accusing him of smuggling marijuana loads and trying to run over a peace officer.

Cases of suspected drug smugglers claiming they were forced into crime by Mexican cartels increased in 2011. But federal authorities have said many claims prove false or cannot be independently verified, typically leading to prosecution against the alleged smugglers.

Even so, sources outside law enforcement give Sanchez’s claim some credence, pointing to a Gulf Cartel lieutenant as the possible person behind the alleged kidnapping of the man’s brother. Those sources say the same high-ranking cartel member — a man known only as Metro-4 — is also likely responsible for other incidents on the U.S. side of the border, including an attempted kidnapping as well as a foiled abduction that resulted in the shooting of an Hidalgo County sheriff’s deputy.

According to court records, Sanchez and 23-year-old Jose Guadalupe Macias Ramirez led authorities on a high-speed chase Dec. 6 near Palmview. Sanchez was at the wheel when he allegedly veered toward peace officers, prompting them to fire nine shots. He avoided capture, leaving behind Macias and a maroon Ford F-150 pickup truck with the letters “CDG” — the Spanish initials of the Gulf Cartel — spray-painted inside. Authorities found the truck to be carrying more than 700 pounds of marijuana.

U.S. Border Patrol agents caught up to Sanchez on Dec. 20 and arrested him after a brief vehicle and foot chase near Abram. While in custody, court records state, he claimed a high-ranking Gulf Cartel member in Reynosa known only as Comandante 4 had coerced him to move the drugs.

Sanchez’s brother Juan Armando Sanchez had been involved in the drug business, according to the account Isaac Sanchez gave authorities. However, Gulf Cartel members came to suspect Juan Armando of stealing $2 million and kidnapped him in October from a Reynosa convenience store.

Cartel members later approached Isaac Sanchez at his home in Mission and threatened to torture and kill his brother unless one of two conditions was met: Either the family must pay a $4 million ransom, Isaac Sanchez told investigators, or he must move 50 drug loads for the Gulf Cartel.

Law enforcement agents who testified during his detention hearing said Isaac Sanchez claimed his mother, who lives in Mexico, received text messages and photos that depicted his brother bound and gagged.

U.S. Magistrate Judge Dorina Ramos ordered the Mission man held without bond, and only time will tell if his claims hold up to scrutiny in federal court. However, sources outside law enforcement but with direct knowledge of criminal activity in northern Mexico said the Gulf Cartel leader to whom he referred was not Comandante 4 but rather Metro-4.

The latter, they said, is a top Gulf Cartel lieutenant from Reynosa who, alongside regional chief of operations Mario Armando “Pelón” Ramirez Treviño, has kept the organization running smoothly since the September death of predecessor Samuel “Metro 3” Flores Borrego, a close associate of the crime syndicate’s current leader, Jorge Eduardo “El Coss” Costilla.

Flores’ slaying, presumably under orders of fellow lieutenant Juan “R-1” Reyes Mejia, led to a schism within the Gulf Cartel that has been directly linked to various criminal acts in the U.S.

The faction led by Reyes, called the Rojos, engaged the rest of the Gulf Cartel, which mostly comprises a faction known as the Metros.

According to new information received from sources outside law enforcement, the Metros control the major cities in the border area from Matamoros, across the border from Brownsville, to Miguel Alemán, across the border from Roma. The Rojos, meanwhile, have entrenched themselves in an area between Rio Bravo, across the border from Donna, and Valle Hermoso, a city about 25 miles southwest of Matamoros. Various groups have capitalized on the infighting by stealing marijuana loads from the syndicate.

A source outside law enforcement described Metro-4 as a man loyal to the Gulf Cartel but ruthless and headstrong — someone who thinks little before resorting to violence. The same source pointed to him as the man behind an explicit order to recover the stolen drugs at all cost as a means of remedying a perceived lack of respect.

That order led to a foiled kidnapping attempt on Oct. 30 that in turn resulted in a shootout that injured an Hidalgo County sheriff’s deputy.

Sheriff Lupe Treviño has said the confusion caused by the internal struggle within the Gulf Cartel allowed drug loads to be stolen. The cartel tasked a group of gang members with tracking the loads and recovering them. When the effort didn’t go as planned, the group kidnapped various alleged drug dealers, leading to the shooting incident.

The same weekend as that episode, two men allegedly working for the Gulf Cartel kidnapped a man in Hidalgo, according to the police department there. They held him for three days and then tied him up and put him in the trunk of a car so a juvenile driver could move him to Reynosa. Police said the captors were under orders to recover a 1,500-pound drug load.