31.   We are operating on heightened security alert.

32.   Washington remained under a heightened security alert, although streets near the White House were reopened and the number of military jets guarding the city appeared reduced.

33.   We are operating on a heightened security alert.

34.   Peacekeepers and logistics staff were allowed to re-enter the base after the all clear was given within an hour of the security alert.

35.   A Chicago-bound American Airlines flight returned safely to Britain on Wednesday after a note found in a seat pocket caused a security alert.

36.   A high state of security alert is being maintained nationwide for the next three months by the police and army.

37.   A NATO base in Macedonia was put on extra security alert Tuesday following two large explosions outside the compound overnight, a spokesman said.

38.   A Northwest Airlines bound for Beijing landed in another Chinese city after a security alert and authorities questioned the passengers and crew, the U.S. airline said Friday.

39.   After a June security alert, the U.S. Embassy suspended consular services for a month.

40.   Airport police said it slipped through when the officer with the dog was abruptly called to a real security alert and forgot to remove the test explosives.