A Chinese tourist is in a stable condition, after surgery to remove a fence post from his chest.
The 17-year-old is now recovering in a ward, and the operation to remove the piece of wood from the left side of his chest was a success, a Waikato Hospital spokeswoman said.
The teenager was sitting by a window at the back of a 20-seater bus when it left the road in the Fitzgerald Glade near Rotorua and hit the wooden fence about midday yesterday.
A batten smashed through the window on impact and impaled the teenager under his armpit.
"It entered through his chest under his arm, and it's almost out through his back,'' Westpac Waikato Air Ambulance pilot Grant Bremner said.
"He was still conscious and still aware of what was going on, obviously it was painful.''
It was believed the tourists were from China, and were heading to Rotorua at the time of the accident.