A police spokeswoman on Saturday said there was no update in their search for her, and work would continue through the day to locate her.
Police have asked anyone who knows where Epiha is, or anyone who may have seen her, to contact them immediately.
She is considered dangerous and members of the public have been told not to approach her, police said.
Anyone with information can contact Counties Manukau Police on 09 261 1321 or by phoning 111.
During an alcohol-fuelled rage, Epiha fatally stabbed 32-year-old mother Alicia Maree Nathan, also known as Robinson, and threatened to kill another woman at an Avonhead, Christchurch, property in August 2017.
Epiha, who was 18 at the time of the attack, was jailed for at least 10 years as part of a murder life sentence last year.
Police were informed immediately after Epiha escaped from Corrections staff, Cave said.
"We have provided them with information to assist them to locate her. We encourage anyone with information about her whereabouts to contact Police on 111.
"The prisoner is likely to be charged with escaping custody, which can result in a maximum sentence of five years' imprisonment.
"A full operational review into the circumstances of the incident is being carried out."