While the United States, North Korea and China prepare for talks to defuse tensions over Pyongyang's nuclear weapons program, worries remain over the North's supposed chemical and biological arsenal.
Diplomats from the United States, North Korea and China meet Wednesday in Beijing to discuss North Korea's nuclear weapons programs, which contravene its treaty commitments to be nuclear free.
Tuesday, the commander of American forces in South Korea, General Leon LaPorte, called North Korea a grave treat to global stability, citing its nuclear ambitions and massive conventional forces.
North Korea has the fifth largest military in the world, still spending more than 30 percent of its economy on defense, despite crippling poverty.
Experts say the North's other weapons of mass destruction also present an immediate threat.
American and South Korean experts and intelligence officials say Pyongyang's chemical weapons include sarin and mustard gases, both deadly.
The North has up to 5,000 tons of chemical agents and it has a biological arsenal includes smallpox and anthrax, according to Park Yong-ok, a retired South Korean army general, and a professor at the South's military academy. He says that while South Korea can protect its military against chemical or biological attack, it can do little to shield its 47 million citizens. "If they really use that weapons, chemical or biological weapons, if they really use that, there really is no effective protective means, he said.
Professor Park added that North Korea has about 10,000 artillery pieces and mobile rocket launchers within reach of the South's capital, Seoul. Their shells can carry chemical weapons. He called that vast battery of guns the North's "greatest weapon."
To use its biological weapons, Professor Park said, North Korea probably would slip special forces troops into South Korea carrying disease agents.
The United States attacked Iraq last month and toppled the Saddam Hussein government because it had not complied with United Nations resolutions demanding that it give up weapons of mass destruction.
There are no such resolutions restricting North Korea's chemical and biological weapons. While Pyongyang has signed a United Nations treaty to bar biological weapons, the treaty does not require inspectors to verify compliance. And North Korea has not signed a U.N. treaty banning chemical weapons.