Two Colombian brothers pleaded guilty Tuesday to U.S. drug trafficking and money laundering charges stemming from their roles as founders of the Cali cocaine cartel, and agreed to forfeit billions of dollars of assets linked to their drug trade.

Gilberto, 67, and Miguel Rodriguez Orejuela, 63, made their pleas in an agreement reached after months of negotiations with several U.S. agencies. The two brothers who once ran the world's top cocaine supplier could now spend the rest of their lives in prison, each receiving 30-year sentences.

A separate deal described in court will protect six of the brothers' relatives in Colombia from prosecution on obstruction of justice and money laundering charges. That agreement also could permit 28 people with ties to the brothers to keep property and other assets not tainted by drug money. The 28 could eventually be removed from a U.S. list freezing their assets and blocking them from doing business with U.S. entities.

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Both brothers spoke briefly in court in Spanish, shackled at the ankles and wearing pinstriped business suits instead of the usual tan prison garb.

Gilberto Rodriguez Orejuela said, "I have admitted to my responsibility willingly" and Miguel Rodriguez Orejuela issued an apology "to the people of the United States and to all individuals in authority. I am doing this from the bottom of my heart."

"They sacrificed themselves for their family," said David O. Markus, attorney for Gilberto Rodriguez Orejuela.

Prosecutors did not comment after the plea hearing but U.S. Attorney General Alberto Gonzales and other top U.S. and Colombian officials planned a news conference in Washington later in the day.

U.S. District Judge Federico Moreno accepted the guilty pleas and approved the sentencing agreement between prosecutors and defense lawyers.

The brothers agreed to forfeit to the United States $2.1 billion in assets linked to drug trafficking, but the two probably made many times that amount during the cartel's heyday in the 1990s. The forfeited assets were detailed in an 11-page list of items and included properties and businesses around the world.

Click here to read Miguel Rodriguez Orejuela's plea agreement (pdf)

Click here to read Gilberto Rodriguez Orejuela's plea agreement (pdf)

Click here to read the family's deal with the U.S. government (pdf)

But neither brother is being required to cooperate in any ongoing or future criminal investigations, according to the plea agreement.

The Cali cartel became the world's leading cocaine smuggling ring after eclipsing the rival Medellin cartel, which fell apart when several top members were arrested and Medellin top kingpin Pablo Escobar was killed in a 1993 shootout with Colombian police.

The Cali cartel was once responsible for as much as 80 percent of the cocaine smuggled into the United States. It was known for its ingenious smuggling methods, hiding cocaine in such things as hollowed-out lumber and cylinders of chlorine, even shipments of frozen broccoli and okra.

Miguel became known as "The Master" for his inventiveness in finding new ways to hide drugs, while Gilberto's nickname was "The Chess Player" for his role as the cartel's strategic thinker. Their family invested in dozens of legitimate businesses around the world, including the Colombian discount drug store chain Drogas La Rebaja.

William Rodriguez Abadia, Miguel's son and Gilberto's nephew, agreed to forfeit about $300 million in worldwide assets after pleading guilty in March to U.S. charges and agreeing to testify against his father and uncle.

The Rodriguez Orejuela brothers were convicted in Colombia of drug charges in 1995, but were indicted in 2003 in Miami on charges that they continued to run their cocaine empire from behind bars. Gilberto Rodriguez Orejuela was extradited in late 2004 and Miguel Rodriguez Orejuela in early 2005, the highest-ranking of more than 300 drug traffickers extradited since the U.S. and Colombia signed a new treaty in 1997.

U.S. Immigration and Customs Enforcement, Drug Enforcement Administration agents and others have investigated the Cali cartel since 1991, resulting in more than 100 convictions, the seizure of more than 50 tons of cocaine and $15 million in cash.

All told, the Cali cartel is estimated to have smuggled more than 250 tons of cocaine into the United States since the 1970s. A recent DEA analysis said that several Colombian organizations now control that country's cocaine trade, increasingly in concert with Mexican organizations that distribute the drug in the United States.

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