OMAHA, Neb. (AP) — A 16-year-old Nebraska high school football player died after a heat-related medical emergency at a practice.

Drake Geiger died Tuesday night after medics were called to South High School, where Geiger had collapsed on a practice field at 4:27 p.m., an Omaha Fire Department spokesman said Wednesday.

Geiger had a pulse when medics arrived and was treated for heat exposure and taken to the University of Nebraska Medical Center, where he died, Battalion Chief Scott Fitzgerald said.

An Omaha Public Schools spokeswoman said the district was investigating the events that led to Geiger’s death and had no further comment.

Nebraska high schools began preseason football practices Monday during one of the most severe heat waves of the summer.

The temperature was 91 degrees with a heat index of 105 at the time Geiger collapsed.

Geiger’s father, Scott Hoffman, told the Omaha World-Herald his son was 6-foot-3 and 389 pounds and had no known medical conditions.

Hoffman told the newspaper his son didn’t practice Monday because his physician forgot to sign a form after Geiger’s physical.

“He was a big kid,” Hoffman said, “but he was a healthy big kid.”

South High principal Jodi Pesek notified parents, students and faculty of Geiger’s death in an email Wednesday. Counselors were made available at the school if students wanted to talk.

Geiger is at least the fourth high school football player in less than a month to die during a practice or conditioning session, according to media reports.

A 15-year-old in Macon, Georgia, died July 26 and a 16-year-old in Philadelphia died July 13, both after exerting themselves in hot conditions. A 15-year-old in Detroit died Saturday while doing conditioning drills with his team, though heat was not mentioned as a possible cause.

A college freshman at Virginia Union died Sunday after collapsing during a football practice. Heat was not cited as a cause.

From 1995-2020, 51 high school football players in the United States died from heat stroke during football-related activity, according to the University of North Carolina’s National Center for Catastrophic Sport Injury Research. There were three deaths attributed to heat stroke in 2020.