A guess at a phone code, from one million possible combinations, ultimately filled in the blanks of real estate agent Yanfei Bao's death

Tingjun Cao has been found guilty of murdering Bao after luring her to a Christchurch property viewing in July last year.

Detective Inspector Nicola Reeve says the breakthrough came from an investigator, who guessed Bao's phone code correctly with two attempts remaining.

She says GPS data led to her being found.

Bao's partner, Paul Gooch is extending gratitude to multiple individuals and organisations, including the Police.

The jury took 97 minutes to find Cao guilty.