LEXINGTON, S.C. — Officials say “multiple factors” contributed to the death of a South Carolina high school football player who collapsed at practice.

News outlets report Lexington County Coroner Margaret Fisher said Tuesday that 14-year-old Lewis Simpkins died of complications from an abnormal heart rhythm caused by a pre-existing heart condition.

Simpkins, a sophomore defensive tackle at River Bluff High School in Lexington County, fell to the ground near the end of a two-hour practice Aug. 10. He later died at a hospital.

The autopsy also showed Simpkins had an enlarged heart and a thickening of the left ventricle.

Fisher says those pre-existing conditions, along with the day’s high heat and humidity, likely contributed to what happened, as did the strenuous physical activity.

The autopsy revealed no signs of dehydration or heat stroke.