Two buses with 61 children on board collide near Lithgow, in NSW Blue Mountains

Two buses with 50 children on board have collided in the NSW Blue Mountains.

One bus rear-ended the second at the intersection of State Mine Gully Road and Old Bells Line of Road at Newnes just before 4pm, police said.

In addition to the 50 children, there were 18 adults on board the buses. 

The crash triggered a major response from police, highway patrol officers, paramedics, fire crews and volunteers.

Police said the worst of the injuries appeared to be bruising.

One woman and three children have been taken to Lithgow Hospital for treatment.

The remaining children will be taken to the same hospital as a precaution.

Police said those involved were from a school in St Marys and were on a holiday excursion. 

The buses appear to be from the children's party company Go Bananas.

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