Police have arrested the man in relation to a historic offence.

A man who flew into Auckland from Korea earlier this week has been arrested in relation to an alleged historic theft, say police.

The man, a Kiwi resident, left South Korea after his mother, stepfather and 14-year-old half-brother were killed.

Detective Senior Sergeant Nadene Richmond said the 35-year-old was arrested at 5.30pm on Sunday and will appear in the North Shore District Court tomorrow. No details of the alleged theft were given.

"New Zealand police is continuing to liaise with Korean authorities and this matter is being treated as a priority," she said. "Extradition proceedings have not been received."

Immigration New Zealand confirmed the man arrived in Auckland on October 24, and was a New Zealand resident.

South Korean police had been working with Interpol to extradite the man back to South Korea. They have not released the man's identity.

The bodies of two of the victims were found at their home on Wednesday, October 18, with multiple stab wounds. A kitchen knife was reportedly found beside them.

The third body was found the next day in the boot of a rented vehicle in a parking lot in Gangwon Province, the Korea Herald reported.

The victims' bodies were discovered with multiple stab wounds, the Korea Herald reported.