Willemijn Vermaat was detained by authorities early on Friday morning but was later released.
Cambodian authorities earlier said there was no direct evidence that Ms Vermaat was responsible for destroying the statue but she confirmed to APNZ today that she had.
Ms Vermaat, who returned to Wellington last night, said she apologised to Unesco for damaging the site.
The site is described by Unesco as "one of the most important archaeological sites in South-East Asia".
Cambodian authorities alleged Ms Vermaat destroyed the statue after she went missing inside the Bayon temple last Thursday night.
A statement from the Apsara Authority said her tuk-tuk driver had asked the local tourist police service for help finding her. She was found early on Friday morning.
Ms Vermaat was detained by police for questioning but was later released, the Cambodia Daily reported.
Shortly afterwards, authorities found the 1m-high Buddha statue had been broken into four pieces at the Bayon temple.
The Apsara Authority then sought to take her back into custody, but she had already left the country.
The Cambodia Daily said the statue dated back to the reign of Jayavarman VII, in the 12th century. It was already broken into several pieces when it was discovered, and was restored in 1988 to be displayed at Bayon.
However, the Phnom Penh Post reported the statue was a replica dating back to 1988. The paper said the temples at Angkor Wat were filled with replicas due to widespread looting and war.
She admitted she had pushed over the statue, saying it "didn't belong" in the temple.
Ms Vermaat said she had been travelling alone and spoke to local police after leaving the temple, who later let her go.
By Brendan Manning and Matthew Backhouse of APNZ
