Crowd in Garland, Texas, Sang National Anthem while Gunfire Exploded in Shootout with Terrorists

Two hundred people broke into "The Star-Spangled Banner" as a deadly gun battle raged outside.

A police officer was shot in the leg by two Islamic terrorists who were in turn mowed down in a hail of gunfire.

It all happened in Garland, Texas, outside Dallas, at an exhibit of cartoons depicting the Prophet Muhammad.

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Tom Trento was hosting an online video stream of the event when a SWAT team rushed in and made a shocking announcement: "A police officer has been shot. Two suspects have been shot - possibly have explosives on him, okay? That's what we're worried about right now. You're not leaving, nobody's going anywhere for a while."

Two hundred people attending the event were escorted to safety and taken to another room.

That's when they launched into "The Star-Spangled Banner"and other patriotic songs while they waited for the 'all clear' signal.

The exhibit was organized by Pamela Geller, a controversial activist who offered a $10,000 prize for the best cartoon of Muhammad. Some call her a provocateur - she says she was exercising her right to free speech.

One CNN reporter told Geller, "There's always this fine line between freedom of speech and being intentionally incendiary and provocative."

Geller responded, "Intentionally incendiary and provocative by drawing a cartoon? This is the low state of freedom of speech in this country."

One slain terrorist was identified as Elton Simpson who posted this message on Twitter before the shooting: "May Allah accept us... #Texasattack."

The Texas attack is being compared with the massacre at the satirical magazine in Paris last January, in which 12 people were killed.

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