They said an orange alert was in effect for trains, buses and the airports.

NPR: New York, Los Angeles Step Up Security

New York City is to remain on Orange alert, and airspace restrictions for Washington and New York introduced during the war against Iraq will remain in place but under review.

CNN: Terror threat lowered to Yellow

New York has been on "orange" alert, or the second-highest level -- indicating a high risk of terror attack -- since the color-coded warning system was established after the September 11, 2001 attacks.

CNN: New York subway system on alert

The volunteer was in serious but not life-threatening condition at Mission Hospital -- "able to move his arms and his legs ... and he is alert, " said Orange County Sheriff's Lt.

CNN: See daring rescue of hiker

Federal officials lowered the nation's health alert level Monday from red, or "high, " to orange, or "elevated, " and said university and secondary students can return to class Thursday while younger students will wait until May 11.

CNN: Mexican citizens to return from China

"Orange" is the second-highest level in the nation's five-tiered, color-coded threat alert system.

CNN: Terror alert level raised to 'orange'