WASHINGTON – As the nation marks the one-year anniversary of Osama bin Laden’s death, travelers should expect an increased security presence on planes and trains.

Metro says there’s no specific or credible threat against the system, but Metro Transit Police understand that al-Qaida has shown interest in anniversaries and significant dates.

Metro Transit Police officers will be on a heightened state of alert throughout the week.

At the airports, the Transportation Security Administration says it remains at a heightened state of vigilance, and the security posture always includes measures both seen and unseen.

Officials say that, as always, travelers should say something if they see something out of the ordinary.

WTOP’s Adam Tuss contributed to this report. Follow Adam and WTOP on Twitter.

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