The witnesses tell Eyewitness News they screamed, but it was too late.
About 45 minutes from Monterrey, one survivor recalled the horror of the deadly crash.
Hilda Cardenas, 65, was left with 52 stitches in her body, and describes the horrifying ride on Tuesday morning in rural Mexico.
Cardenas said from her bed that they were already three hours behind schedule on their bus ride from Houston to Monterrey.
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She was headed back from a routine with her son in Texas. It was just 7 a.m. That is when the other passengers started yelling for the driver to wake up.
Cardenas said the bus flipped and so did the 40 or so people on board.
The bus rolled off the highway. Cardenas said she climbed out a window, and found herself in a small ditch of water.
When she came to her senses, she saw people on the ground around her.
She said she thanks God above to be among the survivors.
Cardenas said she's upset with the bus driver, that he needed to be more cautious.
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