A Rio Grande Valley high schooler witnessed a motorcycle crash, saw a gruesome injury, and helped save a man's life.

For the 16-year-old student, instinct took over when he witnessed the crash.

"We were coming home from school, me and my older brother," 10th grader Eathan Cantu said.

Cantu is a sophomore at the Harlingen School of Health Professions. He remembers the crash as if it happened yesterday.

"It just looked like an explosion happened. Everything had crashed, and it was bad," Cantu said.

He and his brother were driving home when a motorcycle crash stopped them in their tracks. The accident happened on North 77 Sunshine Strip and Commerce Street.

"There's a turn there, and it's like a two-way street, and he couldn't turn enough. So he got chipped by the car, and as soon as me and my brother saw that, we stopped the car, pulled over, and I called the cops," Cantu said.

Cantu said he ran to the motorcyclist who was on the ground. He called 911 and told dispatchers where they were and told them about the man's injuries.

Cantu says he remembers seeing the lower part of the man's leg, just below the knee, was gone.

"I saw bone, I saw everything, but I knew to stay calm in that situation," Cantu said.

Soon after, a bus driver and off-duty Harlingen Police Department officer Steven Benitez showed up.

"I could tell by the amount of vehicles that were stopping and the lights that were coming on, brake lights, was that it was going to be something serious," Benitez said.

Benitez has been with the Harlingen Police Department for 12 years. He also teaches emergency response.

"When I walked up, I saw the injury, noticed it was a pretty severe injury, which is what caused me to head back and grab the tourniquet," Benitez said.

Benitez wrapped a tourniquet around the man's leg to stop him from bleeding out. He says tourniquets should only be used in life-threatening situations.

Channel 5 News learned the man Cantu and Benitez helped survived.

"I go through the same street every day to go home; it's just weird going there and seeing that and, like, having to go through the same street again," Cantu said.

Now both men hope they can one day meet the man they helped save and shake his hand.

Watch the video above for the full story.