Three siblings lived for up to three years with what is thought to be the skeleton of their mother, police in Japan said on Thursday, with a report adding that they believed she had not died but become a god.

The three - two women aged 59 and 52 and their 65 year-old brother - have denied that they conspired to abandon a body, a crime under Japanese law, because they say their 88-year-old mother is still alive.

"Our mother has become a god. She is not dead but is in the process of being elevated into a higher being," they told officers in Usa, southwestern Japan, according to Jiji Press.

A police spokesman said they were awaiting final confirmation but believed the skeleton was that of a woman who would be 88 if she were still alive.

"We discovered today from an autopsy that the skeletonised body is that of a female who died two or three years ago, but we have to wait for the results if a DNA test to confirm her identity," the spokesman said.