"This (lone wolves) is obviously something that the President and his national security team are quite concerned about," White House Press Secretary Josh Earnest told reporters at his daily news conference yesterday.
"The President, I believe on a number of occasions, has noted that the most challenging threat facing our counterterrorism and homeland security officials is disruptive to the activities of a lone wolf," he said.
The FBI has been following up and pursuing investigations of crimes that are committed by a lone wolf, he said.
"That they often find, when they're interviewing people, that people think to themselves -- people express regret that they didn't share something sooner about something that they saw or happened to overhear or otherwise notice," he said.
Also Read
"We certainly want people to be vigilant. This is a very significant challenge, and there's no one on the President's team that would downplay it," Earnest said.
"Efforts to defeat ISIS on the battlefield must succeed. But it will take more than that. We have to be just as adaptable and versatile as our enemies. As president, I will make identifying and stopping lone wolves a top priority," she said.
Earnest said that over the last couple of years, a lot of resources have been dedicated to countering violent extremism. The President has mandated to mobilise resources across the federal government and worked closely with state and local governments to combat violent extremism.
(Reopens FGN22)
Earnest added: "The other thing that the US government has been able to work effectively to do is to partner with technology companies, social media companies and make it harder for those with bad intentions to use social media outlets to inspire people to carry out acts of violence."
Many technology companies have shown in working with the federal government to prevent the tools that they created to promote freedom and communication and openness from being used to inspire people to carry out acts of violence, Earnest said.
"There is a role for Congress to play, and thus far we have not seen enough members of Congress, principally Republicans, step up to the plate and fulfill their responsibility to keep the country safe," he said.
Clinton said the Orlando shooter was a "mad man" filled with hatred.
"On Sunday, Americans woke up to a nightmare that's become mind numbingly familiar. Another act of terrorism in a place no one expected. A madman filled with hate, with guns in his hands, and just a horrible sense of vengeance and vindictiveness in his heart, apparently consumed by rage against LGBT Americans, and by extension, the openness and diversity that defines our American way of life.
Clinton said if elected, she will put a team together from across the government, the entire government, as well as the private sector and communities to get on top of this urgent challenge.
"And I will make sure our law enforcement and intelligence professionals have all the resources they need to get the job done. We and our allies must work hand-in-hand to dismantle the networks that move money, and propaganda, and arms and fighters around the world," she said.
They are slaughtering Muslims who refuse to accept their medieval ways. They are beheading civilians, including executing LGBT people. They are murdering Americans and Europeans, enslaving, torturing and raping women and girls, she said.
Clinton said the threat from ISIS is metastasizing.
"We saw this in Paris. And we saw it in Brussels. We face a twisted ideology and poisoned psychology that inspires the so-called lone wolves, radicalised individuals who may or may not have contact and direction from any formal organisation," she said.