The government of South Korea wants charges laid against Korean officers of charter fishing vessel Oyang 75 after its own investigation into allegations of abuse of crew.
Seoul sent a 16-person delegation to New Zealand to look into claims of labour abuse and underpayment of Indonesian crew members on the Korean-owned ship.
Last year, 32 crew walked off the ship in Lyttelton claiming physical, mental and sexual abuse.
Seoul says Korean officers from the Oyang 75 are to be officially investigated by its police over what it calls acts of violence.
Korean Ambassador Yongkyu Park says the delegation is now in Indonesia where it is investigating how crew are recruited and the systems of paying them.
The Oyang 75 was chartered by New Zealand firm Southern Storm.