A Donna Independent School District bus driver is being called a hero.

His quick actions helped save a stranger's life while he was on the job last week.

Ausencio "Homer" Sustaita has been a bus driver at Donna ISD for only a couple of months. This is the first time in his life, he's had to jump into action to save another driver's life on the road.

It proves that sometimes unexpected heroes show up at the right place and the right time.

It started just like any day for Sustaita. He was on his way to load up kids on his usual bus route until it turned into a life-saving ride.

"I got the hunch to get off the bus," Sustaita said.

On October 23, Sustaita was driving through Val Verde Road and Frontage Road just before 6 a.m. That's when he saw a semi-truck slowing down.

At first, he thought the vehicle had broken down in the middle of the road. Sustaita turned on his flashing lights, got off his bus and went to check on the driver.

"I walked up to the truck and I started knocking on the door and I didn't get no response, and then I started knocking on the window and nothing," Sustaita said.

The blue Kenworth truck came to a complete stop at the intersection, blocking traffic.

"His daughter that was driving behind him, I guess she was following him because, as what I understand is, he was going to drop off the truck at a truck stop," Sustaita said.

The driver was having some kind of medical emergency. Together, Sustaita and the daughter kept him awake until police and first responders made it to the scene.

"[We] started to get him off the vehicle slowly, because he wasn't reacting," Sustaita said.

The driver was taken to a hospital to be treated just in time. Sustaita says he was just doing what he hopes anyone in his shoes would do.

"Evaluate the situation as quickly as possible because in this case, if it was a stroke, every, every second counts and that can make the difference between life and death," Sustaita said.

That morning, his bus route ran a little later than usual, but Sustaita says he was exactly where he needed to be.

The driver's family thanked him for his quick thinking and actions. Sustaita says he's just grateful he was able to save someone else's life.

Watch the video above for the full story.