DENVER -- The parents of Columbine killer Eric Harris said they are "horrified" by the release of a diary their son kept in the year before the school massacre.

Wayne and Kathy Harris released a statement through their attorney Thursday after Westword published sections of the dairy kept by Eric Harris (pictured, left), earlier this week.

Eric Harris wrote of his hatred for people and his relish for violence.

"The Harrises are concerned that the public release of their son's writings and videotapes may inspire further copycat incidents," their attorney said in a statement faxed to 7NEWS.

The couple also said they did not leak the documents, copies of which were in their possession.

A spokeswoman for the Jefferson County sheriff's office said that only the Harris family and the sheriff's office had copies of the documents and the newspaper did not get them from the department.

Sheriff's spokeswoman Jacki Tallman said that certain documents seized from the Harris home (pictured, right) were ordered sealed by court order and had been returned to the family. She said the documents published by Westword appeared to be among those ordered sealed by the judge.

"The copies which Mr. and Mrs. Harris received from the sheriff's department in June differ in appearance in many respects from the copies published by the Denver media," according to the family's statement. It did not explain how they differed.

The diary entries published this week show that Harris planned the attack on his high school with Dylan Klebold for at least a year before the massacre.

Thirteen people died in the 1998 attack, and nearly two dozen others were wounded.

Additional Resource:

• Columbine Memorial Site