Tyrell Edwards, 18, was behind the wheel when his ute went off the road and crashed into a tree about 7.50pm yesterday in Buxton.
All five passengers, friends and students from Picton High, were killed.
Edwards suffered non-life-threatening injuries and was taken to Liverpool Hospital.
He has since left hospital and was arrested in Bargo this afternoon.
He “is assisting police with their inquiries” at Narellan Police Station.
NSW Police Detective Acting Inspector Jason Hogan said Edwards had returned a negative alcohol breath-test at the scene, but results for his mandatory tests were still incoming.
The Nissan Navara being driven by the green P-plater had only enough seats for four people.
“Obviously, having six people in a four-seater vehicle is inherently dangerous and it should not be done,” Hogan said.
The five teens killed have been identified as Summer Williams, Lily Van De Putte, Gabriella McLennan, Antonio Desisto and Tyrese Bechard.
