Harrell has been with the football program for four years but head coach for only one.
Students-athletes, media outlets, and parents have given differing recollections relating to the event, however.
According to a parent of a child who was hospitalized, the task was 300 push-ups in an hour with no break and no water.
"As a parent we send our kids to school trusting that they will be cared for at the highest level. That has been the case until this unfortunate event," the anonymous parent told Fox 4.
That student reportedly suffered from rhabdomyolysis, a condition resulting from the breaking down of muscle tissue that releases chemicals into the blood after continuous stress on the muscles. The condition can cause kidney damage.
A junior captain of the football team states, however, that the coach was not punishing the students, but rather "instilling discipline" and the players were free to leave at any time.
The player, who says water was indeed available, expressed that he is praying for his fellow teammates.
"He’s treated us with nothing but respect and he loves every single one of us like his own," the captain said of his coach.
That player's mother is also defending the coach, saying that she would have been "the first person up at the principal’s office" to shut the program down if she felt the children were being harmed.
According to the Dallas Morning News, a letter sent to parents by the school's principal said that parents need to look out for possible symptoms, such as being "unable to bend or extend arms, unable to lift arms above head," or having "dark urine" or "sharp arm pain."
The letter advised bringing the student to the athletic trainer if any symptoms arise.
In the letter, district administrators say they are taking action "including but not limited to, placing Coach Harrell on administrative leave while the investigation is pending" while notifying the appropriate agencies.
Administrators and campus personnel say they are in contact with the families in question.
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