A man was flown to Providence Alaska Medical Center with serious injuries Tuesday afternoon after an SUV rear-ended a school bus full of children, according to Alaska State Troopers.

The bus driver and 22 students from Big Lake Elementary were taken safely off the bus and none reported injuries following the crash at about 4:15 p.m., said Mat-Su Borough School District spokeswoman Catherine Esary.

The 26-year-old man, who was not immediately named, was reported to be in serious condition when medevaced, troopers spokeswoman Megan Peters said.

The Toyota 4Runner he was riding in was driven by a 23-year-old woman who was taken to Mat-Su Regional Medical Center to be treated for minor injuries, Peters said.

The crash occurred at Mile 212 Big Lake Road. The 4Runner apparently plowed into the back of the bus while it was stopped with its lights flashing on a straight stretch of dry road, Peters said. She said she didn’t know if speed or alcohol were factors.

“We don’t know what the cause was,” Peters said. “We’re going to have to talk with witnesses and everybody else.”

It appeared the 4Runner wound up pinned under the school bus, requiring emergency personnel to undergo an extensive extraction process to get him help. Patty Sullivan, spokeswoman for the Mat-Su Borough, described the scene as “heavy entrapment.”