A witness has described the moment a black Holden Commodore pulled over and then carried out a U-turn - with a bus driving right behind it.
Tokoroa local Pam Bull watched as the bus slammed into the side of the Holden, pushing it through a fence and into a paddock 20m away.
The crash happened around 4.20pm on State Highway 1 near the intersection of State Highway 30, south of Tokoroa.
Four people were injured and the car's driver had to be cut free after the right side of the Holden was smashed up by the bus.
The GoBus had just one passenger who has some cuts on his leg, Bull said.