Young Erick Perez had been playing basketball with his friends in West, Texas when just a few hundred feet away, he saw a fertilizer plant become ablaze. That's when he started shooting video of the scene, just seconds before a massive blast rocked the city. 

"I'm still shaken up ... I haven't stopped shaking since this whole thing happened. This is probably the worst thing I've ever seen in my life," he said.

Up to 15 people could be dead, authorities say, and over 160 people were being treated for injuries sustained in the explosion.

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