The United Nations tightened security at its European headquarters Thursday after receiving a warning that it could be a terrorist target, officials said.
"The Swiss authorities have contacted us to inform of a possible terrorist attack against United Nations premises in Geneva," said an internal memo to UN employees in Geneva.
The memo, obtained by The Associated Press, said: "This attack would take place between Oct. 5 and Oct. 10."
Geneva police spokesman Eric Grandjean said the threat was against "one UN building," but refused to specify whether that referred to the global body's main office in the city, the Palais des Nations, or another building housing an agency such as the World Health Organization or the UN High Commissioner for Refugees.