Jason Paul Somerville says he murdered neighbour Tisha Lowry and his wife Rebecca Somerville, who were found buried under the floorboards of his Christchurch home, because he was angry with them.
The bodies of Mrs Somerville, 35, and Ms Lowry, 28, were discovered at the house in Wainoni Rd in September.
In a brief appearance at the Christchurch District Court on Monday, Somerville, 33, entered guilty pleas to the murder charges and was remanded in custody for sentencing later this month.
Ms Lowry had lived two houses away from Somerville, and her body lay hidden under his house for almost a year after her disappearance.
The police summary of facts states Somerville invited Ms Lowry into his home before strangling her, and burying her body under the floorboards.
Somerville admitted the killings in an interview with police about the disappearance of his wife in September.
The police summary of facts revealed Somerville had violated both women after strangling them.
He told the police he killed Ms Lowry because he had become angry with her, and he also became angry at his wife and killed her after she rejected his sexual advances.
He will appear in the High Court on 27 November for sentencing.
Minister pleased at admission
The minister at a Taupo church formerly attended by Somerville says he is pleased Somerville has admitted the killings.
Keith Harrington of the Taupo Baptist Church says the Somervilles attended his services regularly over about four years and their children are still being cared for by church families.
Mr Harrington says his congregation recently prayed that if Somerville had committed the crimes, he would plead guilty and avoid the trauma of a protracted trial.
Mr Harrington also says while the church is horrified by what's happened, members are still concerned about Somerville.
He is pleased that has now happened, both for the victims' families and for Somerville himself.