Hunter Metcalf said he always looked up to his twin brother Austin, who was born just four minutes before him.

“As a linebacker, he was a stud, and I always tried to fill those shoes and play with him,” Hunter Metcalf told CNN affiliate WFAA. “I had a blast my whole life playing sports with him.”

That bond remained unshakable until the moment Austin Metcalf took his last breath after being stabbed by another student during a high school track meet Wednesday in Frisco, Texas, about 30 miles north of Dallas.

Metcalf told WFAA he tried to save his brother’s life by stopping him from bleeding out. He said he held him until first responders arrived on scene and attempted resuscitation.

“I tried to whip around as fast as I could,” Metcalf said. “I looked at my brother and I’m not going to talk about the rest. I tried to help him.”

First responders administered lifesaving measures, including CPR and giving blood, but were unable to save Austin Metcalf, who died at the scene, Frisco police said in a news release.

In that moment, Metcalf had lost his twin brother and role model. And the Frisco school community had lost a standout athlete with a promising future.

Police say the 17-year-old student at Frisco’s Memorial High School was stabbed after an altercation with a student from another school in the district.

Karmelo Anthony, a 17-year-old student at Centennial High School has been arrested and charged with first-degree murder, police say. His bond was set at $1 million, court records show. Anthony is being held at the Collin County Jail.

Deric Walpole, the attorney representing Anthony, declined to comment Friday.

Andrew Anthony, Karmelo’s father, declined to be interviewed when reached by phone on Friday afternoon.

According to an arrest report, Anthony said “I was protecting myself” when he was approached by a school resource officer near the scene of the stabbing.

A witness told police the altercation started when Austin Metcalf told Anthony to move out from under the Memorial High School team’s tent, according to the arrest report. It was raining during the track meet and athletes were taking shelter, the arrest report said.

A back-and-forth argument between the two teens then escalated. Austin Metcalf touched Anthony, who had just told him, “Touch me and see what happens,” while reaching inside his bag, according to the arrest report. After Metcalf later grabbed Anthony to tell him to move again, Anthony pulled out what the witness recalled as a black knife, stabbed Metcalf once in the chest and ran off, the arrest report says. The knife was later found in the bleachers.

Meghan Metcalf, Austin and Hunter’s mother, said she is grieving the loss of her son.

“My son is not here anymore, and I don’t understand it,” she told WFAA. “He was the most amazing kid. So smart. He had college football guys looking at him to play in college. His goal was to play in college.”

Jeff Metcalf, the twins’ father, set up a GoFundMe campaign, which had raised more than $200,000 as of Friday.

“He was a bright young man with a great future ahead of him,” his father wrote on the fundraiser page. “He was a leader of men. His smile would light up the room. His passion for football was unbelievable.”