The mother of the first student killed in the Columbine High School massacre in 1999 has spoken of how she has forgiven the murderers and met the mother of one of them. 

Beth Nimmo, 63, is the mother of Rachel Joy Scott, who was shot as she sat on a patch of grass eating lunch with her friend. The killers, 18-year-old Eric Harris and 17-year-old Dylan Klebold, shot her three times and moved on when they realised she was still alive. They returned and Harris asked her, "Do you still believe in God?" She answered, "You know I do", whereupon he replied "Then go be with Him" and shot her in the head.

A film based on Rachel's life and death, I'm Not Ashamed, is due to be released on October 21. It is based in part on her journals, found later by her family, in which she expressed a conviction that she had not long to live.

Beth Nimmo told the Daily Mail: "It brings me comfort to know that Rachel died for the one thing she was willing to die defending and that was her faith.

"I believe Rachel had peace when she faced the gun and faced her killer. I can't prove it but I choose to believe that Rachel had peace and that she went from the presence of evil to the presence of the Lord in that split second."

She blames the actions of Klebold and Harris on the bullying she believes they suffered and promotes an anti-bullying campaign, Rachel's Challenge.

She says she has forgiven the killers, who both shot themselves after killing 13 people and injuring 20 others.

"We did make a conscious choice to forgive. Forgiveness is a process of healing," she said.

"It doesn't matter to the boys if we practise forgiveness. But if you aren't able to forgive it creates a life sentence for you. It locks you down to that moment in time when you were violated, when you were hurt.

"For Rachel it was a life sentence. It was over. I choose not to make it my life sentence by letting go of those boys.

"Forgiveness is me saying, what you did to me is not okay but I choose to forgive you because I'm not going to live in the pain of that for the rest of my life. You're not going to control me because I'm not going to let what you did to me define me for the rest of my days."

Beth has also met Sue Klebold, Dylan's mother, who after the massacre wrote to the family of each victim.

The two met several months later. Sue Klebold has also written a book about the events, with profits donated to mental health charities.