Kirk Lankford, convicted of the April 2007 murder of Japanese visitor Masumi Watanabe, must spend at least 150 years behind bars for the killing.

The Hawaii Paroling Authority made that decision today, Prosecuting Attorney Peter Carlisle announced in a courthouse press conference.

In a written statement released this afternoon, parole board chairman Albert Tufono said that while "the circumstances surrounding the case are very complex ... Mr. Lankford's behavior after the victim died displayed a high degree of coldness and callousness.

"This unconscionable behavior is viewed very seriously by this parole board. Accordingly, to ensure the future protection of the community, provide some solace to the victim's family, and assess a punitive consequence, the parole board has determined that Mr. Lankford must spend at least 150 years incarcerated for his crime."

Lankford's lawyer, Donald Wilkerson, was not immediately available for comment.

Carlisle called Lankford, 24, "a textbook sociopath" and said the decision means Lankford won't be able to ask for a reduction in his minimum sentence until he has served one-third of it — 50 years from now.

Carlisle said he notified the parents of Watanabe this morning of the decision in a telephone call to Japan.

Mrs. Watanabe "was overcome with emotion," Carlisle said.

At trial and before the parole board, Lankford admitted striking Watanabe with his truck, but claimed she was only slightly injured by the collision. The shy, 21-year-old jumped out his truck as he was trying to drive her to her home, striking her head on a roadside rock and dying, Lankford claimed.

He carried the body around in his work truck for a day and tried unsuccessfully to bury the body later that night, Lankford testified. He said he then wrapped the body in a garbage bag, carried it several hundred yards offshore of a Windward Oahu beach and then released it.

The remains of Watanabe were never recovered.