Overflow crowd shows up for Dallas blood drive after cops' murders

(FOX NEWS)- The Red Cross was quickly overwhelmed with the response to its blood drive in Dallas following an ambush that killed five police officers and wounded seven more.

So many people showed up that organizers had to turn some people away.

The first donor was a police officer, the Red Cross said.

The Red Cross said that the blood drive was planned ahead of last night's tragic attack.

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