A church bus carrying around 15 people, primarily children, rolled over in northeast Houston on Sunday, according to the Harris County sheriff.

Of the 15 passengers on board, 14 were taken to local hospitals with “possible, but non-life-threatening injuries,” Harris County Sheriff Ed Gonzalez tweeted on Sunday afternoon. One adult, a 33-year-old, was in stable condition.

Gonzalez said there were three adults and 12 kids riding the bus at the time of the crash.

This information came after initial reports were unclear on exactly how many people were on board the bus during the accident since it stopped to drop people off and pick others up. Early estimates reported by Gonzalez via Twitter suggested that there were anywhere from 15 to 25 people on board, while one news outlet reported that there were 16 people.

No other vehicles were involved, although much is still unclear about what caused the crash.

The driver, 42, is believed to have caused the accident by “fail[ing] to control speed while negotiating the curve [which] caus[ed] the bus to roll on its right side,” according to the sheriff’s tweets.

Gonzalez said that the driver was not injured and did not appear to be intoxicated.

One woman told local news outlets that her grandchildren were involved in the crash.

“My grandson’s girlfriend was pinned under, they had to cut her out,” she said. “I don’t know how she’s doing. My grandson, my youngest one, is fading in and out of consciousness, I don’t know how he is. They just took the other one, and my grandson’s friend, they’re all at another hospital, so we don’t know how anybody is.”

The accident occurred near an apartment complex, some residents of which sprang into action to assist those on the bus.

Jennifer Guerra, who was eating breakfast at the time, explained that it all felt surreal when she and her family rushed onto the scene.

“You know basically trying to keep them calm, but it was like crazy. I’ve never seen anything like that,” she said.