Auckland police have released CCTV footage of a man on the run since an attack on his stepmother and her brother several days ago.
Aran Jenkanying and his sister Arunee, both in their fifties, were severely beaten with a stick at a house in Otara on Wednesday morning.
Mr Jenkanying is in Auckland Hospital with head injuries and is not expected to survive.
A warrant has been issued for the arrest of Ms Jenkanying's stepson, Patrick Young, 42.
He may be driving a white 1997 Toyota Corolla, registration WE4878.
Police are urging anyone with information to contact the Otara station.
