Leaders of a Colombian rebel group branded as terrorists by the United States were charged with kidnapping Americans and trafficking in drugs in federal indictments unsealed Wednesday.

Some charges could carry the death penalty, Attorney General John Ashcroft said.

"Today marks another significant milestone in the war against terrorism and drug trafficking in the Americas," Ashcroft said at the Justice Department.

The charges mark the latest in a flurry of U.S. efforts to dismantle rival factions in the 38-year-old Colombian civil war and stem the South American nation's lucrative cocaine trade. Federal officials say the groups use cocaine sales and ransom demands to fund their war efforts.

The indictments were brought against members of the Revolutionary Armed Forces of Colombia, or FARC, which is battling the Colombian government and an outlawed paramilitary group. The State Department lists FARC as a foreign terrorist organization.

One indictment charges Jorge Briceno Suarez, described as the overall military commander of FARC known as "Mono Jojoy," of conspiring in 1997 to kidnap Americans Jerel Shaffer and Earl Goen from a fishing camp in neighboring Venezuela.

Shaffer was beaten and held hostage in Colombian jungles for nine months, until a $1 million ransom was paid. Goen was released shortly after the kidnapping.

Briceno Suarez, a commander named Thomas Molina Caracas -- also known as "Negro Acacia" -- and one unidentified FARC member known only as "El Loco" were also charged in that kidnapping, which could bring the death penalty because of the ransom demand and because two Colombian people were murdered while Shaffer was held hostage, Ashcroft said.

Briceno Suarez's brother, German Briceno, was indicted on U.S. charges in May in the same case.

Another indictment unsealed Wednesday charges Henry Castellanos Garzon, described as a senior FARC commander called "Romana," in the 1998 kidnappings of Americans Louise Augustine, Todd Mark, Thomas Fiore and Pete Shen during a Colombian bird-watching trip. They were released after a month without payment of any ransom.

A third indictment adds Briceno Suarez to a list of FARC members charged in March in a conspiracy to distribute cocaine in the United States.

Briceno Suarez, Caracas and Garzon and the unidentified suspect are at large. FBI Director Robert Mueller said U.S. authorities will work closely with the Colombian government to "pursue these terrorists with the same intensity that was demonstrated in the investigation that led to today's indictments."

The indictments come a week after the Justice Department announced it had disrupted a drugs-for-weapons plot involving the United Self-Defense Forces of Colombia, a paramilitary group fighting FARC in the civil war. Carlos Castano -- the leader of that group, known as the AUC -- was charged in September with exporting 17 tons of cocaine into the United States and Europe.

Last spring, a federal grand jury returned indictments against FARC itself and six of its members in a 1999 conspiracy to kidnap and kill Terence Freitas, Ingrid Washinawatok and Lahee'Enae Gay, all Americans who were working with a group of poor Colombians. They were all slain.