The spring issue of ‘Inspire’, a magazine published by Al Qaeda, shows a picture of a San Francisco Airport shuttle car with a caption about assembling a bomb.

The spring issue of ‘Inspire’, a magazine published by Al Qaeda, shows a picture of a San Francisco Airport shuttle car with a caption about assembling a bomb.

"The quote below the photo reads, "Stand up, pack your tools of destruction. Assemble your bomb, ready for detonation."" [KBCW]

Authorities are taking the photo seriously, but do not believe it is meant as a specific threat.

Rather, they see it as propaganda intended to motivate its readers to become active.

In general, the publication targets Muslim extremists and serves as a do-it-yourself guide to terrorist activity.

It is always under close watch by US officials, but the fact that it featured transportation that serves a major international airport has troubled some.

At this time there are no known threats to San Francisco, but vigilance is being advised.

Said a member of the House Committee on Homeland Security, "Be alert, note your surroundings, and appreciate that there are still people out there who wish to do us harm."

He does not believe that there is a need to alter regular commuting patterns.