WASHINGTON (CNN) -- One of the world's most wanted drug lords was captured Wednesday aboard a recreational fishing boat off Mexico's Baja peninsula, federal law enforcement officials said.

The Drug Enforcement Administration's Michael Braun described the man captured, Javier Arellano-Felix, as "one of the most ruthless thugs that was involved in drug trafficking around the world."

Law enforcement officials say Arellano-Felix led a violent Tijuana-based cartel that brought multi-ton shipments of marijuana and cocaine into the United States and trained body guards and assassins to protect turf and eliminate rivals.

"We feel like we've taken the head off the snake," said Braun, the DEA's chief of operations. "This is not your average arrest ... It's what our job is all about. It's what we live for."

The Arellano-Felix organization was responsible for a recently discovered, elaborately constructed tunnel under the Mexico-California border, law enforcement officials said.

And, Deputy Attorney General Paul McNulty said, the cartel was sophisticated enough to negotiate directly with Colombian drug lords and paramilitary groups for multi-ton shipments of cocaine.

The DEA lists rewards of $5 million each for the capture of Arellano-Felix and his brother, Eduardo, who federal officials said plays a lesser leadership role in the cartel.

Gone fishing

Coast Guard Commandant Thad Allen said the DEA alerted him Monday morning that intelligence showed Arellano-Felix was aboard the chartered 43-foot recreational fishing vessel Dock Holiday, 15 miles off the coast near La Paz, Mexico.

Arellano-Felix was traveling under an alias, but eventually confirmed his identity, officials said. Eight other adults and three juveniles also were detained.

Officials said two of the men in custody are believed to be Arturo Villareal-Heredia and Marco Fernandez, both described by the DEA as "assassins" for the Arellano-Felix organization. Authorities said the two will initially be held as material witnesses, but later will be charged with conspiracy to distribute narcotics and other counts.

Arellano-Felix is in the custody of the U.S. Coast Guard on board the cutter Monsoon. He will be brought ashore in San Diego, where he has been indicted and will be arraigned.

His brother and several other indicted cartel members remain at large.

2003 indictment

According to the DEA's Web site, members of the Arellano-Felix organization were named in a July 2003 indictment alleging federal racketeering offenses, conspiracy to import marijuana and cocaine and launder money.

The indictment also listed 20 murders in the U.S. and Mexico as part of the conspiracy, McNulty said.

The Arellano-Felix organization, often referred to as the Tijuana Cartel, was considered one of the most powerful and violent drug trafficking organizations in Mexico, according to the DEA.

At the beginning of 2002, the cartel was dealt two blows, the DEA said: Ramon Arellano-Felix, the cartel's enforcer and assassin, died in a street fight with drug trafficking competitors and Mexican police. A month later, Benjamin Arellano-Felix, who the DEA says played the role of the cartel's CEO, was arrested by the Mexican Military.

The loss of two cartel leaders was "the beginning of the end" for the organization, the DEA's Braun said. With Javier Arellano-Felix's capture, he added, "We've got this brutal organization in a choke hold."