[WASHINGTON] Homeland security and terror threats are back on the front burner for the presidential campaign after an explosive device blew up in New York City on Saturday night, injuring 29 people, following incidents in New Jersey and Minnesota earlier in the day.
Republican presidential nominee Donald Trump seized on the New York blast within hours as part of his public safety-oriented message, even front-running authorities in declaring that a "bomb" had gone off.
Tim Kaine offered a measured response, taking his cue from remarks made late Saturday by Hillary Clinton, the Democratic presidential nominee.
Mr Kaine, Mrs Clinton's running mate, said on CNN's "State of the Union" that the New York blast "raises the stakes on the need to be really, really smart in dealing with challenges like this, both with the law enforcement community but also to make sure we're doing what we can to stop any lone wolf attacks in the United States."
On NBC's "Meet the Press," Mr Kaine said the developing events show the value of having Mrs Clinton, the former secretary of state, in the White House. "It's really important. And I would say experience really matters," he said, adding that strong alliances international and intelligence sharing are also key to combating terror threats.
New Jersey Governor Chris Christie, who's also chairman of Mr Trump's transition team, said on CNN that "if you look at a number of these incidents, you can call them whatever you want. They are terrorism, though. There's no doubt about that. They are terrorism."
The New York incident was "obviously an act of terrorism" yet doesn't appear to be tied to international terrorism, New York Governor Andrew Cuomo said at a briefing on Sunday.
Also on Saturday, a man armed with a knife was shot to death by an off-duty police officer after reportedly mentioning "Allah" while stabbing eight people in a St Cloud, Minnesota, shopping centre. The alleged stabber was "a soldier" of the Islamic State, media linked to the jihadist group said on Sunday.
The latest string of domestic security incidents could overtake contretemps about Mr Trump's comments on President Barack Obama's citizenship and Mrs Clinton's bout of pneumonia as top campaign issues in the run-up to the Nov 8 election.
On "Fox News Sunday", Mr Christie said that the explosion in a trash can when a 5K foot race was about to start in Seaside Park, New Jersey, was "clearly an act of terrorism, we just don't know who was responsible. It was done to terrorise the people in New Jersey." He said the FBI was leading the investigation along with the Department of Homeland Security and other agencies.
"We have some promising leads, but no suspects at this time," Mr Christie said on CNN.
Kicking off a rally in Colorado Springs, Colorado, on Saturday night, Mr Trump announced that "a bomb went off in New York" before it was confirmed to have been an explosive device. He then used the incident to drive home his message.
"We better get very tough, folks," Mr Trump said. "It's a terrible thing that's going on in our world and in our country and we are going to get tough and smart and vigilant." Mr Trump tweeted Sunday morning, "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."
Mrs Clinton told reporters on her campaign plane on Saturday that she has been briefed about the bombings and the attack in Minnesota, and said she is in touch with the mayor's office in New York. She said she'd have more to say when she has the facts.
"Obviously we need to do everything we can to support our first responders, also to pray for the victims," Mrs Clinton said. "We have to let this investigation unfold.''
Mr Christie defended Mr Trump's initial comments on the incident, saying on CNN, "I don't think you have to defer when saying that there was an explosion and a bomb in New York. I mean, everybody knew that. It was being reported on television." "You shouldn't attribute it to any particular organisation or group if you don't have the facts or information to do that," Mr Christie said.
"What Donald did was perfectly appropriate to tell that group in Colorado Springs that a bomb had exploded."