Obama did not found ISIS.
"So, I said, 'the founder of ISIS", Trump continued.
Even while working to restore confidence in his campaign, Trump appeared to court controversy anew when he said late Thursday that he was open to trying Americans suspected of terrorism at the Guantanamo Bay detention center in Cuba.
Russian Prime Minister Dmitry Medvedev made similar remarks late a year ago, although both Russian leaders sounded more measured in their comments than Trump, placing more blame on USA policies for fostering ISIS than on Obama personally.
Noting that his opponents had signed but not kept their word, Trump said it was a "funny thing" because the pledges were signed "so that I would sign them".
The White House has declined to comment on Trump's claims.
"We're going to win so big", Trump told a roaring crowd one month ago at the Republican National Convention.
"I would say they could be tried there", Trump said, referring to Guantanamo Bay.
She did not provide any new policy ideas, instead focused picking at the GOP's Presidential nominee personality and how his economic plan will not work.
Hewitt noted that Obama has waged an effort against the Islamic State: "He's not sympathetic to them". "Regardless of party, voters are increasingly concerned that Mr Trump's tendency to bully, demean and degrade others sends the wrong message to our children", Clinton campaign chairman John Podesta said.
Federal law generally prohibits US citizens from being prosecuted in military tribunals.
He appeared to be mimicking the argument that the USA troop's withdrawal from Iraq under Obama with Clinton serving as secretary of state created a vacuum that allowed the Islamic State group to emerge and flourish in Iraq and Syria. The terrorist group, in its current form, was officially founded by the group's current leader, Abu Bakr al-Baghdadi. The group began as Iraq's local affiliate of al-Qaida, the group that attacked the USA on September 11, 2001.
Trump said he wasn't anxious Republicans would cut him off - and threatened to stop fundraising for the party if they do. The officials weren't authorized to comment publicly and requested anonymity.