WASHINGTON (AP) — The accused leader of a Mexican drug trafficking cartel who authorities say once maintained close ties to Joaquin "El Chapo" Guzman pleaded guilty in federal court Tuesday, admitting that he helped ship tons of cocaine from South America to the United States.

The plea from Alfredo Beltran Leyva, who was captured in Mexico in 2008 and extradited two years ago, comes weeks after Guzman, the notorious drug kingpin, was captured by Mexican authorities following a prison escape.

Though the plea resolves the case without a complete presentation of evidence, prosecutors said in court documents that they were been prepared to show that Beltran Leyva sold drugs to U.S. gangs in exchange for weapons, commanded squads of hit men that tortured and murdered rivals and paid bribes to Mexican government officials. One witness could have testified that he saw Beltran Leyva return from a meeting with Guzman wearing a tactical vest containing grenades, court filings show.

"For decades, Alfredo Beltran Leyva helped to lead one of the world's most notorious drug cartels, causing widespread violence and disrupting lives," Attorney General Loretta Lynch said in a statement.

The Beltran Leyva organization was led by Alfredo and his brothers as it grew to prominence as an arm of Guzman's Sinaloa Cartel. The Beltran Leyva group smuggled drugs and ran human trafficking operations, along with enforcement operations for the larger Sinaloa organization.

That relationship soured, according to federal prosecutors, after Alfredo Beltran Leyva's 2008 arrest. His brothers blamed Sinaloa leaders for his arrest, and the split eventually led to a bloody fight among the two groups. At the same time, the Sinaloa cartel was waging a war against the Juarez cartel for control of drug and human smuggling routes in northern Mexico.

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 arrest of Alfredo Beltran Leyva was among the early take-downs of cartel bosses by Mexican authorities in their fight against the criminal syndicates that started in the early days of former President Felipe Calderon's term.

Guzman is currently in Mexican custody, though the government has expressed willingness to extradite him to the U.S., where he faces multiple indictments.

It was not immediately clear what Beltran Leyva's plea means for Guzman if and when he is brought to the United States. But his former position as a trusted ally almost certainly means he has a wealth of information about the inner workings of one of Mexico's most powerful drug cartels.

Michael Vigil, a former chief of international operations for the Drug Enforcement Administration, said at one time Beltran Leyva handled logistics and bribery payments to public officials for the Sinaloa Cartel and he and his brothers helped the cartel expand the territory it controlled.

Vigil added that after the brothers' split with Guzman and the Sinaloa Cartel, they aligned themselves with former rivals from the Juarez Cartel and eventually Los Zetas, a ruthless gang that once served as the enforcement arm for the Gulf Cartel. Those relationships may also make Beltran Leyva a valuable witness in other pending cases.