John Lennon's killer has been denied parole for the ninth time.

The New York Board of Parole said in a statement: "In spite of many favourable factors, we find all to be outweighed by the premeditated and celebrity-seeking nature of the crime.

"From our interview and review of your records, we find that your release would be incompatible with the welfare of society and would so deprecate that seriousness of the crime as to undermine respect for the law."

His application was denied by a three-person panel, despite acknowledging his strong "institutional records and rehabilitative efforts".

It was recently revealed five people had written letters to the board pleading for his release.

Chapman's petition for parole has come up every two years since 2000 but has been rejected each time.

His next hearing is scheduled for August 2018.

Chapman, an obsessed fan of John and The Beatles, pleaded guilty to second-degree murder after shooting the singer four times in the back as he arrived at his Upper West Side apartment with his wife, Yoko Ono, 83.

The artist recently admitted she is "super careful" even when she's in her apartment after John's assassination nearly 36 years ago.

She said: "I'm super careful, almost like a certain animal who is used to being hunted, like a deer. So when I go out or when I don't go out, in my apartment, I'm very, very careful.

"It's very, very difficult for me to think about Chapman, especially because he doesn't seem to think that was a bad thing to do. It's crazy."