WASHINGTON, Jan 10: The United States is keeping eight airports and other unspecified facilities on high alert for terrorist attack, after lowering the general threat level to "elevated" from "high", US media reported on Saturday.

Announcing the lowering of the threat level Friday, after 19 days of intense nationwide security precautions, Homeland Security Secretary Tom Ridge said that the US would, however, "maintain particular vigilance around some critical resources and locales."

He said most of the increased security would involve "the private sector" including airlines. Sources said the facilities included eight airports, including those in Washington, New York, Los Angeles and Las Vegas.-AFP