The US State Department is ordering non-emergency government personnel to leave the US Consulate in Lahore, Pakistan.
A US official said the departure has been ordered because of a threat specific to the Lahore mission.
The official, who requested anonymity, says the action is a precautionary measure and is not related to the recent closures of several US diplomatic posts in the Muslim world.
In a travel warning issued last night, the State Department advised American citizens to defer all non-essential travel to Pakistan.
Officials say the presence of several foreign and indigenous terrorist groups poses a potential danger to US citizens throughout the country.