By Jonathan Dienst, Joe Valiquette and Alice McQuillan
NEW YORK -- Nearly a full day after the explosion in Times Square, law enforcement officials said they had no suspects.
Four men trying to cross the border attempted to flee the checkpoint as Canadian officials tried to question them, investigators said.
But after Thursday morning’s explosion, FBI, NYPD and Homeland Security officials are reaching out to Canadian authorities to try to learn more about the men who were at the border crossing last month.
"We cannot allow this to happen to the men and women serving in our military whether they are at home or abroad," McCain said.