KUWAIT CITY (AP) – Several swine flu cases have been detected among U.S. soldiers passing through Kuwait, officials said Saturday.

The soldiers were treated on a U.S. base and some of them have left the country, the state news agency quoted a Health Ministry official as saying. The official, Ibrahim Abdul-Hadi, did not say how many soldiers were infected or where they were traveling from.

The U.S. Embassy said cases have “tentatively” been confirmed without providing details. It said the soldiers did not come into contact with the Kuwaiti population.

“Each case was characterized as being a mild flu-like symptom,” the American military said in a statement. “All but … a couple have been treated and returned to duty.” No further details were provided.

Oil-rich Kuwait is an ally of Washington and a logistics base for U.S. military personnel serving in Iraq.

The Kuwaiti health official said no other swine flu cases have been detected in the country.

The World Health Organization’s global tally now stands at 12,022 cases of swine flu and 86 deaths in 42 countries. More than half of those cases have been reported in the United States, while most of the deaths occurred in Mexico. The virus was first detected last month.