JILL MAHONEY and KATHRYN BLAZE CARLSON The Globe and Mail
Published Thursday, Jun. 06 2013, 6:00 AM EDT
Last updated Thursday, Jun. 06 2013, 6:17 AM EDT
“As an investigator, you always talk about tunnel vision and I think it’d be tunnel vision for me to say that I definitely believe there’s a third person or to say there wasn’t,” Staff Sergeant Matt Kavanagh said Wednesday. “It’s possible that there’s only two involved and it’s also possible that there may have been a third. And so we’re looking into that and we still have some doors to shut, some avenues of investigation.”