Security Minister Rosa Icela Rodríguez told reporters Friday that a small Cessna airplane carrying Zambada, 76, and Guzmán, about 37, took off from Hermosillo airport in northern Sonora state just before 8 a.m. Thursday and landed at around 10 a.m. at the international airport in Santa Teresa, N.M, near El Paso, Texas. The men were promptly arrested by DEA and FBI agents.

The U.S. Embassy didn’t notify Rodríguez until 3:30 p.m. local time, she said. President Andrés Manuel López Obrador wasn’t informed until 4:14 p.m.

U.S. authorities have not said why they kept the plan from their Mexican counterparts. But U.S. anti-drug operations have been foiled in recent years by leaks from Mexican officials, leaving Washington wary.

“We are awaiting official communication on whether what happened yesterday was a capture or surrender,” Rodríguez said during López Obrador’s daily news conference. “This is part of what the U.S. government must tell us.”

There were conflicting accounts of whether Zambada, a co-founder of the Sinaloa cartel, was fooled into boarding the U.S.-bound plane, or whether he intended to give himself up. An official from the Department of Homeland Security, as well as a former Justice Department official, said he was tricked.

Zambada was told he was being taken to look at investment properties, said the former official. U.S. agents had to scramble to get to the Santa Teresa airport airport because they didn’t expect the ruse to work, the ex-official said. Both officials spoke on the condition of anonymity to discuss the sensitive case.

Guzmán cooperated in the operation, the former official said. Guzmán is one of the “Chapitos,” the four sons who took over their father’s business after El Chapo was arrested in 2016. His brother, Ovidio Guzmán, was captured by the Mexican army in 2023 and extradited to the United States.

Zambada and “El Chapo” Guzmán, who is serving a sentence of life plus 30 years in the federal supermax prison in Florence, Colo., jointly led one of the world’s most prolific drug cartels. The Sinaloa federation was a multibillion-dollar business that exported heroin, cocaine, methamphetamine and other drugs and is credited with building the fentanyl business. The Biden administration has targeted the cartel as it tries to combat the most deadly drug epidemic in history.

U.S. authorities from President Biden on down described the operation as a resounding success. But analysts said the arrests were unlikely to cripple the narcotics business and could escalate violence in Mexico.

“When we look at organized crime from the outside, we like to talk about the big cartels,” said Falko Ernst, senior Mexico analyst at the International Crisis Group. “But behind that there is a very large number of other operators that never give themselves a name, that never pop up in media reporting, that aren’t publicly identified.”

They include logistical operators, cooks and others who bribe state and local officials, he said. “And that is the real backbone of this economy.”

With the Sinaloa cartel weakened, its rival, the Jalisco New Generation Cartel, is likely to fill any voids in the fentanyl business, analysts said. That group will increasingly challenge Sinaloa for dominance, said Vanda Felbab-Brown, a senior fellow at the Brookings Institution who studies Mexican criminal organizations.

“The whole of Mexico can be inflamed,” she said. The Jalisco cartel is viewed as more violent than Sinaloa, which sought pacts with Mexican government and security officials. “The criminal market run by Jalisco is much worse than a criminal market run by El Mayo,” she said.

Zambada was less well-known than El Chapo Guzmán, a larger-than-life figure who inspired movies and books with his flashy lifestyle and uncanny ability to tunnel out of prisons. Yet the low-key Zambada was equally important; some Mexican security officials believed he had long been a bigger player in the cartel than his partner. (His nickname, “El Mayo,” refers to his middle name, Mario, according to Mexican media reports).

Zambada appeared in federal court in El Paso on Friday morning, and pleaded not guilty, according to court records. His attorney, Frank Perez, did not immediately respond to a request for comment.

Zambada and the elder Guzmán were indicted in El Paso with 22 other high-ranking Sinaloa Cartel members in 2012. Zambada was charged with being part of a conspiracy to traffic cocaine and marijuana into the United States, launder money and murder perceived enemies.

The younger Guzmán was en route to Chicago, where he was set to make his first court appearance on Tuesday, U.S. officials said. He is to be represented by one of the attorneys who defended his father, at El Chapo’s narcotics trial in Brooklyn in 2019. “I’ve got no comment other than to confirm I represent Joaquin and will be in court for him at his initial appearance,” attorney Jeffrey Lichtman said.

The “Chapitos” were among the U.S. government’s most-sought drug-trafficking targets; Washington has offered a reward of up to $10 million for information leading to the arrest or conviction of the two oldest brothers, Iván and Jesús Alfredo, and a $5 million award for the younger brother, Joaquín. Yet Joaquin was the least involved in drug trafficking of all the brothers and could secure a deal for leniency for himself and his brother Ovidio.

Ivan is now considered the undisputed leader of the Sinaloa cartel, said the former U.S. Justice Department official.

The operation to bring the traffickers to the United States was so secret that their names were kept off the flight manifest filed shortly before the plane took off, Rodríguez said. The plan named only the pilot, Larry Curtis Parker, she said. He was listed in migration records as a visitor to the country, and wasn’t registered as a U.S. Embassy employee or U.S. government agent.

Rodríguez was peppered by reporters Friday on why Mexico wasn’t told in advance about such a critical operation. Zambada also faces arrest warrants in Mexico.

Rodríguez insisted that cooperation with Washington against the illegal drug trade is strong.

“We are going to continue cooperating with the U.S. government, as we have done up until this event,” she said.

Zambada was seen as a sophisticated operator who had cultivated extensive political ties over the years. Even if his arrest unleashes violence among Mexican criminal groups, the United States could ultimately benefit if he cooperates in naming corrupt current and former Mexican officials, said Felbab-Brown.

“I’m sure a lot of political actors and government officials did not sleep a wink last night,” she said. “He knows where all the bodies are buried over many administrations.”

Miroff and Ovalle reported from Washington. Spencer S. Hsu in Miami, Lorena Rios in Monterrey, Mexico, and Alejandra Ibarra Chaoul in Mexico City contributed to this report.