The only time people attribute their actions to their religion is in the case of Islam, which actually commands its followers to be violent, something the media conveniently overlooks.
This killer never attributed his attacks to Buddhism, and in fact the only thing that might be deduced was that he was motivated by a racial obsession, since all of his victims but one were white and he supposedly took the time to pick them out and aim at them rather than just shooting indiscriminately.
What he really was, of course, was crazy, and crazy people often go with some political or external obsession to justify their craziness to themselves. But he was obviously also trying to use Buddhist meditation as a sort of self-treatment mechanism. Clearly, it didn’t work; however, it was certainly not the cause of his rampage.
Do you have a citation on that? This is an important fact.