Both presidential candidates called the explosion that occurred Saturday night in New York City a "bomb" or "bombing" --a description that authorities did not use in early part hours of the investigation.
At least 29 injured were injured in Manhattan's busy Chelsea neighborhood.
As news was trickling in of the incident, the Republican nominee told supporters at a Colorado rally that "a bomb went off."
"I must tell you that just before I got off the plane, a bomb went off in New York and nobody knows exactly what's going on. But, boy, we are really in a time - we better get very tough, folks," he said.
Officials have said it's too early to determine the cause of the blast and there has been no confirmation that the incident was linked to terror.
I would like to express my warmest regards, best wishes and condolences to all of the families and victims of the horrible bombing in NYC.— Donald J. Trump (@realDonaldTrump) September 18, 2016
Trump offered his condolences to victims on Sunday morning.
Democratic nominee Hillary Clinton was more cautious but also described the explosion as a bombing.
Speaking to reporters on her campaign jet, she said: "I've been briefed about the bombings in New York and New Jersey," she said, referring to both the NYC blast and a pipe bomb that went off Saturday in New Jersey before a Marine charity run.
In response to a reporter question about her reaction to Trump's use of the word bomb as the cause of the explosion, Clinton replied that "it's important to know the facts about any incident like this."
"I think it's always wiser to wait until you have information before making conclusions," she added.
Many were critical of both candidates and how they responded.
Reason #723 why Trump shouldn't be POTUS: based on early reports of explosion in NYC (could be gas leak?) he assumes terror; vague threats.— Scott Gunn ن (@scottagunn) September 18, 2016