All samples of the killer influenza virus sent outside the United States have been destroyed except one in Lebanon (search), and that has been located, the U.N. health agency said Wednesday.

The sample that had gone missing in Beirut "was found at the airport," said Maria Cheng (search), spokeswoman for the World Health Organization. "That will be destroyed soon."

Previously unaccounted for samples sent to Mexico and South Korea also have been destroyed, she said.

Because of fears of a global pandemic should the virus be released, WHO (search) has been urging destruction of the 50-year-old H2N2 virus. The kits were sent to 61 laboratories in 18 countries outside the United States.

Cheng said South Korean officials had previously reported to WHO that they had destroyed half the samples they had been sent, but hadn't confirmed that they had also destroyed the other half. The destruction of all the samples sent to South Korea has now been confirmed, she said.

A missing shipment to Mexico has been tracked down in a warehouse, has also been destroyed, she added.