WASHINGTON -- A man accused of being the leader of a Mexican drug-trafficking cartel pleaded not guilty Monday in federal court after being extradited to the United States.

Alfredo Beltran Leyva was held without bond and faces a detention hearing on Friday.

U.S. and Mexican authorities say the Beltran Leyva gang was responsible for trafficking drugs to the United States and Europe including cocaine, marijuana, heroin and methamphetamine. Prosecutors say Beltran Leyva led the drug trafficking organization with his brothers.

The 43-year-old was extradited to the U.S. on Saturday and made his first U.S. court appearance before Magistrate Judge Alan Kay.

A one-count indictment accuses Leyva of conspiring to import to the U.S. more than 11 pounds (5 kilograms) of cocaine, 110 pounds (50 kilograms) of methamphetamine, 21 pounds (10 kilograms) of heroin and 2,000 pounds (907 kilograms) of marijuana. He entered the not guilty plea through his court-appointed lawyer.

When Beltran Leyva was arrested in 2008, he was alleged to be a top lieutenant of the powerful Sinaloa cartel, commanding squads of hit men and organized drug shipments north.

The gang split from Sinaloa and later had its stronghold between Acapulco and the south of Mexico City, while retaining some drug routes in western Mexico. They were known particularly for infiltrating or buying off government officials and police.

Leyva's alleged participation in the conspiracy began in 2000 and continued until his indictment in 2012.

The Beltran Leyva gang started to split apart in late 2009, when one brother, Arturo, who took over for Alfredo, was shot dead by Mexican marines and another brother, Carlos, was detained two weeks later. Another brother, Hector, was arrested in San Miguel de Allende in October.

The Levya cartel has distributed tens of thousands of kilograms of dangerous narcotics and engaged in a campaign of violence that sparked drug wars and jeopardized public safety across North America, said Assistant Attorney General Leslie Caldwell.

With the takedown of the Beltran Leyva leadership, the cartel has splintered into untold numbers of gangs that terrorize central and southern Mexico, including the states of Morelos and Guerrero south of Mexico City.

- Associated Press writer Pete Yost and Katherine Corcoran, AP chief of bureau for Mexico and Central America, contributed to this report.