"In many respects, you know, they honor President Obama," the U.S. Republican presidential nominee said. "He is the founder of ISIS."
He repeated the allegation three more times for emphasis.
Trump also pointedly referred to the president by his full legal name: Barack Hussein Obama.
The presidential nominee has also accused his opponent, Democrat Hillary Clinton, of founding the militant group. As he shifted the blame to Obama on Wednesday, he said "crooked Hillary Clinton" was actually the group's co-founder.
Trump has long blamed Obama and his former secretary of state — Clinton — for pursuing Mideast policies that created a power vacuum in Iraq that was exploited by ISIS, another acronym for the group. He's sharply criticized Obama for announcing he would pull U.S. troops out of Iraq, a decision that many Obama critics say created the kind of instability in which extremist groups like ISIS thrive.
The White House declined to comment on Trump's accusation.
ISIS began as Iraq's local affiliate of Al-Qaida, the group that attacked the U.S. on September 11, 2001. The group carried out massive attacks against Iraq's Shi'ite Muslim majority, fueling tensions with Al-Qaida's central leadership. The local group's then-leader, Jordanian-born Abu Musab al-Zarqawi, was killed in 2006 in a U.S. airstrike but is still seen as ISIS' founder.
Trump's accusation — and his use of the president's middle name, Hussein — echoed previous instances where he's questioned Obama's loyalties.
In June, when a shooter who claimed allegiance to ISIS killed 49 people in an Orlando, Florida, nightclub, Trump seemed to suggest Obama was sympathetic to the group when he said Obama "doesn't get it, or he gets it better than anybody understands." In the past, Trump has also falsely suggested Obama is a Muslim or was born in Kenya, where Obama's father was from.
The president, a Christian, was born in Hawaii.
Trump lobbed the allegation midway through his rally at a sports arena, where riled-up supporters shouted obscenities about Clinton and joined in unison to shout "lock her up." He railed against the fact that the Orlando shooter's father, Seddique Mateen, was spotted in the crowd behind Clinton during a Monday rally in Florida, adding, "Of course he likes Hillary Clinton."
Sitting behind Trump at his rally on Wednesday was former Rep. Mark Foley, R-Fla., who resigned in 2006 after allegations he sent sexually suggestive messages to former House pages.
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