According to the Los Angeles Times, tattoos plus “certain biographical details” were the source of that conclusion. A representative of the Sikh congregation, Kanwardeep Singh Kaleka, told CNN that “members described the attacker as a bald, white man, dressed in a white T-shirt and black pants and with a 9/11 tattoo on one arm.”
There has already been widespread speculation that the shooter may have intent on committing an anti-Islamic hate crime but confused Sikhs with Muslims because of their turbans. Kaleka pointed out that “maybe it’s because the ladies were fortunate enough to dodge it out, but so far most of the people I’ve heard have been shot and killed were all turbaned males.”
An unidentified federal official, however, told the Times that there was not yet enough evidence to conclude that the gunman was a member of a hate group or other group dedicated to violence. “The investigation will have to continue to see and determine the motive,” the official stated “We don’t know much about the motive at this point.”