Police are asking drivers not to pick up hitchhikers on the Desert Road or Turangi township in the central North Island following the escape of a dangerous prisoner.
Christopher Watkins was jailed in 1988 and is serving a life sentence for murder at Tongariro-Rangipo Prison.
The Department of Corrections says the prison gate was unlocked and Watkins simply walked out while carrying out his duties as groundsman.
Prison staff noticed him missing about 1pm on Thursday.
Police say they do not know which direction Watkins would have headed but say he should not be approached.
Watkins is described as Pakeha, 1.65 metres tall and of average build. He was last seen wearing a green polar fleece top.