The failure to provide any description of the shooter is suggestive; either the police are unsure as to who the shooter was or, perhaps, they have an idea but are holding it back for public safety concerns? From the Star:
"Homicide detectives have a description of the shooter, he said, but he wouldn't elaborate. The police gang squad was also inside the centre, which was closed until further notice.
Marcus Neves-Polonio, an employee at the Eaton Centre food court near the Dundas and Yonge Sts. entrance, described the male shooter.
“The shooter was yelling, going crazy,” he said. “It was just nuts.”
Neves-Polonio, who said he was crouching barely a metre away from the fracas, said the shooter was wearing a dark hoodie and baggy pants."