Dozens of kids involved in NSW bus crash

A nine-year-old boy has been airlifted to hospital with serious head injuries after two school buses crashed south of Wollongong.

Forty students from the private Illawarra Christian School were on board when the buses collided on Tongarra Road, Albion Park, on Tuesday afternoon.

The boy, who was reportedly ejected from one of the buses, was taken to Wollongong Hospital by ambulance rescue helicopter in a serious condition.

Five other children were taken to the same hospital with injuries including bruising and fractures.

Police say the drivers of both buses will be taken to Shellharbour Hospital for mandatory blood and urine testing.

In a statement on its Facebook page, the school said two Premier Illawarra buses were involved in the accident - one headed to Shell Cove and Flinders, the other to Warilla.

"Children on these routes will be late in arriving home. All parents of children have been contacted," the school said.

Tongarra Road remained closed between Croome Road and the Illawarra Highway on Tuesday evening.