NASHUA, N.H. (AP) — A New Hampshire man charged in a deadly home invasion and machete attack says he fantasized about torturing and killing his mother from age 14 on because she abused him.

Twenty-one-year-old Christopher Gribble testified Monday that his mother used to pin him down and painfully pop acne on his back and pull hairs from his head.

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His mother testified earlier Monday that she once spanked him hard enough to break the wooden spoon she was using. But she denied other things he told mental health counselors about past abuse.

WBZ-TV’s Kate Merrill reports

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Gribble has admitted stabbing Kimberly Cates to death and trying to kill her daughter in their Mont Vernon home in 2009. He has pleaded not guilty by reason of insanity.

He says he thought often about taking his mother to the woods and cutting off little pieces of her to hear her scream.

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