The United States has filed new charges against Mexico's top drug lord and other drug cartel leaders for smuggling billions of dollars worth of cocaine across the border, but they remain at large, U.S. authorities said on Thursday.

U.S. officials announced the charges in New York and Chicago against Joaquin Guzman, Mexico's most wanted man, and other accused leaders, high-ranking members and associates of several of Mexico's most powerful drug cartels. In all 44 people from the United States and Mexico were charged.

Guzman, known as Shorty, is at the center of the violent drugs war that has killed more than 13,000 people in Mexico in the last three years. He and some of the others faced previous U.S. drug trafficking charges.

The United States, aiming to crack down on escalating drug trafficking and violence along the border with Mexico, seeks the forfeiture of more than $5.8 billion in drug proceeds as part of the charges.

The cartels whose alleged leaders are charged today constitute multibillion dollar networks that funnel drugs onto our streets, U.S. Attorney General Eric Holder said.

The indictment accuses Guzman, along with Ismael Zambada Garcia and Arturo Beltran Leyva, of being among the most powerful drug traffickers in Mexico. Also indicted was Vicente Carrillo Fuentes, the alleged head of the Juarez drug cartel.

If captured and convicted, all but one of the defendants face up to life in prison.

Guzman, the leader of the Sinaloa cartel, is the drug gangster most responsible for the wave of killings in Mexico in recent years as he tries to expand his empire to other parts of the country like Ciudad Juarez on the border with Texas.

He escaped from a high-security jail in Mexico in 2001 in a laundry van shortly before he was due to be extradited to the United States.

According to the charges, the defendants were responsible for smuggling into the United States nearly 200 tons of cocaine and large amounts of heroin between 1990 and the end of last year.

The U.S. Drug Enforcement Administration (DEA) estimates that some 90 percent of the cocaine that comes into the United States enters through Mexico.

Holder and Michele Leonhart, the DEA's acting head, told a news conference the United States has offered a reward of up to $5 million for information leading to the arrests of each of the accused Mexican drug cartel leaders.

Let me make something very, very clear here; these are not symbolic acts that we are taking today. Our intention is to indict these people, to get these people to the United States and to put them in jail for extended periods of time, Holder said.

According to the charges, the cartel leaders employed hitmen who carried out hundreds of acts of violence in Mexico, including murders, kidnappings and torture.

The defendants were accused of importing cocaine from Central and South American countries through Mexico and into the United States using cargo aircraft, submarines, container ships, fishing vessels, buses, rail cars, trucks and automobiles.