After putting out an urgent call for blood donations, centers around El Paso were filled with volunteers rushing in to help in the wake of Saturday's mass shooting at a Walmart. 

Vitalent Blood Services said it had sent out more than 240 units of blood to hospitals, but its centers quickly filled to capacity and they can't take any more donors Saturday. 

"We will need your precious donation going forward for ongoing victim needs and to replenish supplies," Vitalent - El Paso posted on Facebook

The organization encouraged potential donors to make a donation at bloodhero.com or by calling 1-877-258-4825. 

If you’re able to donate blood in the El Paso area, Vitalent Blood Services has two locations at 424 S Mesa Hills and 133 N Zaragoza. Additionally, they'll be set up at Abundant Living Faith Center at 1000 Valley Crest from 9 a.m. to 5 p.m. 

"Trust me, your donation will be as valuable the upcoming week as it is today!"

Residents were quick to answer the call for help Saturday afternoon, a video posted on Twitter showed a line to donate stretching out the door of one blood donation center. 

While emergency donations are important during times like these, Vitalant had noted just two days before Saturday's shooting that it takes 24-48 hours to process blood for hospital use so when disasters or emergencies strike, it's the blood already on hospital shelves that save lives. 

"Regular blood donors ensure that there is blood available when its needed," Vitalent tweeted. 

In North Texas, Carter BloodCare said they sent blood products to help treat today's victims as well. 

"While donors have helped rebuild our supply, many of our loyal platelet donors boosted the supply and we were able to send the products needed. We need help," Carter BloodCare tweeted Saturday night. The group encouraged potential donors to visit one of their centers or call 800-366-2834 for an appointment. 

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El Paso, which has about 680,000 residents, is in West Texas and sits across the border from Juarez, Mexico.