A fast-acting child was credited as a hero Monday for grabbing the wheel of a runaway school bus and steering it into a pillar after the driver apparently left the bus to fill up with gas and take a bathroom break.

After all the chaos, 15 students suffered only minor injuries.

"This kid did some quick thinking," said Larry Gray, a fire department spokesman.

The bus, carrying 27 children in kindergarten through seventh grade, started rolling down a hill away from the gas station across the street from Progressive Field, home of the Cleveland Indians.

The gas station's manager, Conner Strickland, said the driver had purchased $40 of diesel for the bus, and was in the bathroom when the bus started to roll. He said he banged on the door to alert the driver, then chased the bus with another employee.

Authorities said the child took the wheel to keep the bus from going farther down the hill, and drove it into a bridge support pillar, where it crashed.

The children jumped out of the side door and landed in the street, said Strickland. "I'm surprised none of them got hit. There was a lot of traffic," he said.

Gray said none of the children's injuries were life-threatening, and all were released after treatment. The driver the was taken to a hospital with chest pains, Gray said.

The driver and firefighters from a station at the top of the hill helped the children off the bus. Most just had bumps and bruises, Strickland said. "I thought it was going to be worse than that," he said.

It wasn't immediately clear why the bus started rolling down the hill. Authorities were investigating.

The bus was carrying students to Arts Academy, a charter school, Gray said. Officials at the school declined to comment. The bus is operated by Aqua Limousine Ground Transportation, he said. A message seeing comment was left with the company.

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