Two young children critically injured in a Waikato two-car collision this morning were not in approved children's car seats, police say.
Two SUVs - a Kia Cerato and a Toyota Hilux towing a trailer - collided on State Highway 27 at Patetonga, north of Morrinsville, about 5.40am.
Acting District Road Policing Manager, Senior Sergeant Jeff Penno said the trailer being towed by one vehicle was carrying another vehicle, and ended up on its side in the accident.
The family of four inside were all hospitalised.
"The two children ... were not restrained in approved car seats and have suffered critical, and serious to critical injuries," Mr Penno said.