MIAMI , Florida ( CNN ) -- A former kingpin for a Colombian drug cartel pleaded guilty Tuesday in U.S. District Court to charges of drug trafficking , obstruction of justice by murder and racketeering , federal officials said . Authorities say Montoya , known as `` Don Diego , '' was the head of the Norte del Valle drug cartel . Diego Leon Montoya Sanchez had faced 15 criminal charges , said Montoya 's Miami attorney , Bill Clay . `` As is often the case in plea agreements , there are concessions and benefits a defendant gets , '' Clay told CNN . `` There are benefits that are very valuable to Montoya . Twelve counts will be dismissed at the time of sentencing . '' Montoya 's plea covered two federal cases . In one , prosecuted by the U.S. attorney 's office in Miami , Montoya admitted to one count of conspiracy to import more than 5 kilograms ( 11 pounds ) of cocaine into the United States and one count of obstruction of justice by murder , federal officials said . In the second case , prosecuted in the District of Columbia , Montoya pleaded guilty to one count of conspiracy to engage racketeering . That case was transferred to Miami for the plea . Sentencing is set for October 21 , Clay said . By statute , Montoya could be sentenced to life in prison , but he will not , the attorney said . He said he believes prosecutors will ask for a 45-year sentence . Federal officials lauded the plea agreement Tuesday . `` This notorious leader of the extremely violent Norte Valle Cartel is where he belongs : behind bars for murder , drug trafficking and racketeering , '' acting Drug Enforcement Agency Administrator Michele M. Leonhart said in a news release . Montoya , 48 , had a $ 5 million reward on his head before his capture in Colombia in September 2007 and extradition to the United States 15 months later . He had been on the FBI 's 10 Most Wanted list since 2004 . Authorities say Montoya , known as `` Don Diego , '' was the head of the Norte Valle drug cartel . The FBI called the cartel `` the most powerful and violent drug trafficking organization in Colombia . '' The Justice Department said Tuesday that , `` based upon FBI estimates , at its peak the Norte Valle Cartel was responsible for 60 percent of the cocaine exported from Colombia to the United States . ... ( B ) etween 1990 and 2004 , the Norte Valle Cartel exported more than 1.2 million pounds , or 500 metric tons , of cocaine worth more than $ 10 billion from Colombia to the United States . '' Even though he did not have to , Montoya chose to make a statement to Judge Cecilia M. Altonaga , the Colombian 's attorney said . `` He said to the judge he wanted to express remorse to his family and to the families of the victims of his criminal conduct , '' Clay said . Montoya is the fourth member of his family to be convicted as part of the Florida case , officials said Tuesday . A brother pleaded guilty in January to one count of conspiracy to import more than 5 kilograms of cocaine into the United States and one count of obstruction of justice by murder . He was sentenced to 30 years in prison . In November 2005 , officials said , another brother and a cousin each pleaded guilty to one count of conspiracy to import more than 5 kilograms of cocaine into the United States . Each received a sentence of more than 20 years .
Former agent for Colombian drug cartel pleaded guilty in U.S. District Court . ' Leon ##or ##z had $ 5 million reward on his head before his capture . FBI calls it ` ` most powerful and violent drug trafficking organization in Colombia ''