FORT WORTH, Texas — Dallas activist groups demanded at a press conference Monday that authorities thoroughly investigate the possibility that the May 6 mass shooting in Allen was a racially motivated hate crime. “Despite killer’s racist content targeting Indian women among other groups, local law enforcement downplays role of targeted racism and hate in the devastating mass shooting,” a press release signed by multiple advocacy groups said. Authorities have not officially determined the gunman’s motive for the May 6 shooting that killed eight people and injured seven at the Allen Premium Outle...