NEW BROCKTON, Ala (AP) — An autopsy found that an Alabama high school football player, who collapsed during summer practice, died from congestive heart failure, the county coroner announced Thursday,

Semaj Wilkins, a 14-year-old freshman at New Brockton High School, died in August after collapsing at the start of afternoon football practice.

The autopsy, performed by the Alabama Department of Forensic Sciences, “determined that the cause of death was congestive heart failure due to cardiomegaly with biventricular hypertrophy, resulting from a coronary anomaly,” Coffee County Coroner Arnold Woodham wrote in a news release. The death was classified as natural, he said.

The Mayo Clinic’s website defines cardiomegaly as an enlarged heart and ventricular hypertrophy as a thickening of the heart walls. The condition can cause the heart to fail to pump blood efficiently.

“Our thoughts and prayers remain with the Wilkins family during this difficult time. We also extend our support to the faculty, students, and staff of New Brockton High School,” Woodham wrote.

New Brockton is a town of about 1,400 people located about 80 miles (130 kilometers) south of Montgomery.