Witnesses still struggling one year after deadly Yonge Street van attack in Toronto
by from on (#4DKYV)
![B88675690Z.1_20190421151541_000_GIQIK4OT](http://media.zuza.com/f/2/f209dcdf-ac09-47c6-b332-40f780b220a2/B88675690Z.1_20190421151541_000_GIQIK4OT.3-0_Content.jpg)
Mental health experts say witnesses may be grappling with secondary trauma on the anniversary of the attack that left 10 killed and 16 others wounded.