Osama bin Laden

NEW YORK (CNN) -- Terrorism suspect Osama bin Laden tried to develop chemical weapons to use against U.S. troops in the Persian Gulf, a high-ranking CIA official said.

Bin Laden's drive to obtain the chemical weapons could be linked to the Al-Shifa pharmaceutical plant in Khartoum, Sudan, which was bombed by the United States in late August, said John Gannon, chairman of the CIA's National Intelligence Council.

Gannon made the comments Monday during a conference on biological and chemical weapons at the Hoover Institution in California.

"We know that bin Laden's organization has attempted to develop poisonous gases that could be fired at U.S. troops in the Gulf states," Gannon told the conference attendees.

'An ominous pattern'

Gannon said the Sudan plant had known ties to bin Laden. The discovery at the plant of a precursor to the deadly gas known as VX fit into "an ominous pattern we had been piecing together against bin Laden and his network," Gannon said.

Gannon: "Clear and present danger ..." ( 374 K/17 sec. AIFF or WAV sound)

In court documents unsealed earlier this month, U.S. prosecutors charged that bin Laden had made efforts to obtain the components of chemical weapons as early as 1993.

He was charged with masterminding the August bombings of the U.S. embassies in Kenya and Tanzania that killed 263 people. Several of his alleged co-conspirators are in custody in New York and in Germany, but bin Laden remains at large.

Washington has offered a record $5 million for bin Laden's arrest and conviction for the bombings.

U.S. prosecutors have said in court documents that bin Laden and members of his militant Islamic organization, Al-Qaida, had plotted attacks against U.S. troops in the Gulf region. Gannon took the allegations a step further, charging that chemical weapons would have been used in the attacks.

Bin Laden, an exiled Saudi Arabian businessman who is believed to be the sponsor of a worldwide terrorist network, issued death threats against U.S. personnel as part of his campaign to drive the United States out of Saudi Arabia following the Gulf War in 1991.