The grandparents of teen gunman Tim Kretschmer have made a tearful apology to the victims of the school shooting – but are still dumbfounded as to why their beloved grandson would kill 15 people in cold blood.

Ruth K. (82) and her husband Wilhelm (80) say they still cannot grasp the tragic events which hit Winnenden in Germany on Wednesday, when 17-year-old Kretschmer went on a killing spree.

School shooting Germany massacre leaves 15 dead How could such a sweet-looking boy go on to carry out such a brutal string of murders? 1 / 2 vorheriges Element nächstes Element

With tears in their eyes, the couple – along with Tim’s great uncle Hermann A. (76) - spoke to BILD about their grandson.

They said there was no prior warning as to what the teenager was going to do: “He was such a lovely chap. He still used to eat Sunday lunch with us. There were roasts with spätzle [south German dough balls] and sauce. He liked it so much."

Ruth and William K. were sitting in the darkened living room where they had affectionately helped to bring Tim up. Pictures of the teen gunman as a child were hanging on the walls.

Granny Ruth said: “Up until kindergarten he was often here, he spent a lot of time with us. His parents were at work a lot.

“His favourite game was with a ball. I stood at the bottom of the cellar stairs, Tim above, and he would throw the ball down to me."

The events at Albertville School in Winnenden are still difficult for Ruth to fathom: “He was a completely normal, quiet boy with us. We cannot grasp it yet.”

Tim’s last visit to his grandparents was with his parents on the Sunday before the tragedy. Wilhelm said: “Tim was quiet, but not quieter than usual. He lay with the cat on the ground and cuddled it. He always liked doing that.”

The family ate together at the table, like so often. First there was lunch, then coffee and cake.

Nobody noticed anything amiss with Tim.

“Also, as he went, we didn’t notice anything remarkable,” Ruth said. “’Bye Granny,’ he said. Exactly the same as always."

Wilhelm added: “We have already racked our brains about whether there was something. But here was nothing.”

When Tim talked with his grandparents, it was often about table tennis, and Ruth and Wilhelm described him as a good brother who would look out for his sister.

But did they know about his passion for weapons?

“No, he did not talk about that much. He grew up with that. His father had already taken him at 14 to the shooting club.

“But the weapons at home were always properly locked away.”

Only great uncle Hermann A. felt at one point that all was not well with Tim: “It was in the middle of February. He sat with us in the armchair, and hardly said anything, he was remarkably reserved. I have still thought about whether I should have spoke to him. But I did not do it.”

The day of the school shooting started like any other. “His parents did not see him on the day. They left the house early to go to work. Tim slept longer as he didn’t have to be at school until later. Also he probably did not see his sister before he left.”

Did they believe he had planned the school shooting for a long time?

Hermann said: “I am sure me that he had already prepared it for several weeks in his head.”

Tim went on to carry out one of the bloodiest killing sprees Germany has ever seen.

“Why he did it is a mystery, and will always remain a mystery,” Wilhelm K. said.

“We will try to keep good memories of him,” Ruth added, “as we knew him.”

Was there something they wanted to say to the families of the victims and the whole world?

The grandparents cried silently. Eventually, Hermann finds his voice - moving words of a desperate family: “One would like to apologize above all, even it was Tim who did it. It has left all his relatives in tears that such a thing happened, that so many young people had to die, that we cannot grasp it at all."

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