Washington ? U.S. officials announced charges Wednesday involving alleged plots to sell drugs to finance weapons purchases for Osama bin Laden’s al-Qaida organization and a Colombian paramilitary group.

The separate cases show the threat to national security from the “toxic combination of drugs and terrorism,” Atty. Gen. John Ashcroft said.

One set of charges involves a plot by four people, two of them Houston-based, to trade $25 million in cocaine and cash for a huge cache of weapons to be sent to the United Self-Defense Forces of Colombia, or AUC, as the 8,000-member paramilitary group is known by its initials in Spanish.

U.S. authorities said the four suspects believed they were going to trade the money and cocaine for 9,000 AK-47s and other assault rifles; grenade launchers and nearly 300,000 grenades; 300 pistols; shoulder-fired anti-aircraft missiles and about 53 million rounds of ammunition.

In the second case, three people are charged with trying to sell heroin and hashish to buy four shoulder-fired Stinger anti-aircraft missiles for the al-Qaida terror network. An indictment says the al-Qaida link was provided by the suspects themselves.

In the Houston case, called “Operation White Terror,” undercover agents videotaped meetings in London, the Virgin Islands and Panama City at which the defendants allegedly discussed exchanging drugs and cash for weapons headed for the AUC, Ashcroft said.

The AUC is the umbrella group for right-wing paramilitaries blamed for most of Colombia’s massacres and hundreds of assassinations. The State Department considers the AUC and the two main left-wing guerrilla armies it opposes to be terrorist organizations.

The AUC’s leader, Carlos Castano, already is charged in the United States with exporting 17 tons of cocaine into the United States and Europe.

The four suspects were charged in Houston with conspiracy to distribute cocaine and conspiracy to provide material support and resources to a foreign terrorist organization. The charges could carry up to life in prison, Ashcroft said.

Two suspects were identified as Uwe Jensen, 66, and Carlos Ali Romero Varela, 43, both of Houston. There was less detail on two others: Carlos Lopez and an individual identified only as “Commandant Emilio.”

In the San Diego case, Ashcroft released an indictment against two Pakistanis and one U.S. citizen originally from India who have been held since Sept. 20 in Hong Kong. They allegedly sought to sell 600 kilograms of heroin and five metric tons of hashish in the San Diego area and use the money to buy Stinger missiles.

The three suspects in custody in Hong Kong were identified as Syed Mustajab Shah and Muhammed Abid Afridi, both of Pakistan, and Ilyas Ali of Minneapolis.

They appeared Tuesday in a Hong Kong court to fight extradition to the United States. Hong Kong, a former British colony now under Chinese rule, has an extradition treaty with the United States.