MEXICO CITY — Mexican marines hauled the captured boss of the Gulf cartel before television cameras on Thursday, in a new blow to a drug smuggling gang already weakened by a brutal war for the US market.

The navy said one of the most wanted criminals, Jorge Eduardo Costilla Sanchez, alias "El Coss," was detained by the marines Wednesday evening in Tampico, a Gulf of Mexico coastal city in the northeastern state of Tamaulipas.

A 41-year-old former municipal police officer, the mustachioed, portly suspect wore a bullet-proof vest, a checkered long-sleeve shirt and blue jeans as he stood stone-face in front of news camera, flanked by masked marines.

"Jose Eduardo Costilla Sanchez was at the top of the cartel considered the second-most powerful criminal organization in the country," navy spokesman vice admiral Jose Luis Vergara told a news conference.

Some 30 marines chased a carload of gunmen on Wednesday to a house in Tampico, where they caught Costilla Sanchez, who did not resist, Vergara said. Five other people were arrested in the operation.

The navy said it seized two large weapons, four smaller guns, 24 clips, 460 bullets of various calibers, three vehicles and expensive jewelry.

Hours before the arrest, five men identifying themselves as Costilla Sanchez's bodyguards were caught in another Tamaulipas town, Rio Bravo, near the Texas border.

Costilla Sanchez was on Mexico's list of most wanted kingpins, with a $2.2 million bounty for information leading to his capture. US authorities offered a $5 million reward and a US federal court in Texas has a warrant for his arrest.

With this arrest, 23 of the 37 most wanted men in Mexico have now been either killed or captured.

The US Drug Enforcement Administration, which works closely with Mexican authorities, called the arrest "significant."

"DEA congratulates the government of Mexico and their brave military for their continued success in apprehending top drug traffickers," said DEA spokeswoman Barbara Carreno.

The navy said "El Coss" led "violent clashes" between the Gulf cartel and their former enforcers, the Zetas, in the states of Nuevo Leon and Tamaulipas. The two gangs have fought a bloody turf war since breaking ties in 2010.

Analysts say some 60,000 people have been killed in Mexico's drug war since 2006, when President Felipe Calderon deployed 50,000 troops across the country to fight the cartels.

Costilla Sanchez's arrest leaves the Gulf cartel leaderless and paves the way for an all-out war for national dominance between the Zetas, founded by former elite troops, and the Pacific coast's powerful Sinaloa cartel, analysts said.

"This is the beginning of a reconfiguration of organized crime in Mexico, with the strengthening of two important organizations, Sinaloa and the Zetas, and the weakening of the rest," Guadalupe Correa, an expert on Mexican drug trafficking at the University of Texas at Brownsville, told AFP.

The latest arrest came a week after marines captured the alleged leader of another Gulf cartel faction, Mario Cardenas Guillen, known as "El Gordo" ("The Fat One"), also in Tamaulipas.

The cartel split after Cardenas Guillen's brother, Antonio Cardenas Guillen, or "Tony Tormenta," was killed in a shootout with Mexican troops in 2010, according to the navy.

One side remained loyal to the Cardenas family while the other side pledged allegiance to "El Coss."

Costilla Sanchez joined the Gulf cartel in the 1990s when it was headed by another Cardenas brother, Osiel Cardenas Guillen.

Osiel Cardenas Guillen was captured in 2003 and extradited four years later to the United States, where he is serving a 25-year prison sentence.