Some U.S. offices abroad closed for security

WASHINGTON (CNN) -- The U.S. Consulate General in Osaka, Japan, closed Wednesday after employees received a suspicious letter, and the U.S. Embassy in Sarajevo also decided to close because of a "credible security threat," State Department spokesman Phil Reeker said. He would not discuss details of the threat.

He said the letter was turned over to police for testing, and employees who handled it were taking antibiotics. The consulate, which covers the Osaka-Kobe district, will remain closed Thursday, but is providing emergency services. Reeker said he knew of no other similar incidents at U.S. posts.

Security at the embassy in the Balkans is being evaluated, Reeker told reporters. Also closed as a precaution were U.S. offices in the Bosnia-Herzegovina cities of Banja Luka and Mostar, including the office of the U.S. Agency for International Development in Tuzla.

Some other posts were closed overseas Wednesday as they evaluated their security procedures, Reeker said. He said embassies and consulates were given guidance on beefing up security, especially at the 200 posts where visas are issued.