PORTLAND, Maine — Donald Trump continued to say on Thursday that he has seen video footage taken by the Iranian government that shows the United States delivering $400 million in cash in January, even though his spokeswoman confirmed Wednesday night that the Republican nominee had instead seen footage of three released American prisoners arriving in Switzerland.

"It was interesting because a tape was made. Right? You saw that?" Trump said to a crowd of nearly 2,000 in Merrill Auditorium on Thursday afternoon. "With the airplane coming in — nice plane — and the airplane coming in, and the money coming off, I guess. Right? That was given to us — has to be — by the Iranians. And you know why the tape was given to us? Because they want to embarrass our country. They want to embarrass our country. And they want to embarrass our president because we have a president who's incompetent. They want to embarrass our president.

"I mean, who would ever think they would be taking all of this money off the plane and then providing us with a tape? It's only for one reason. And it's very, very sad."

Trump first mentioned this footage from the Iranian government during a rally in Daytona Beach, Fla., on Wednesday. Several senior U.S. officials involved in the Iran negotiations told the Associated Press they weren't aware of any such video, and there was speculation that perhaps Trump saw it during one of the classified security briefings provided to presidential nominees, although those briefings have not yet begun. Secretary of State John F. Kerry, who was traveling in Argentina on Thursday, told reporters that he was unaware of any such video, according to the Associated Press.

Late Wednesday night, Trump spokeswoman Hope Hicks responded to an email from The Washington Post that asked if the footage Trump was referencing was actually widely shown video of a private plane landing in Switzerland in January with three American prisoners who had just been released by Iran, including Washington Post reporter Jason Rezaian.

"Yes," spokeswoman Hope Hicks wrote in an email. "Merely the b-roll footage included in every broadcast."

Hicks has yet to respond to a series of follow-up questions.

At the rally in Maine, Trump said that he and Democratic nominee Hillary Clinton will soon receive a classified security briefing, even though he said Clinton should not be trusted with such information.

"Hillary Clinton, furthermore, can never be trusted with national security — can't," Trump said, as the crowd started to chant: "Lock her up! Lock her up! Lock her up!"

"In fact, we're both supposed to be briefed in the not so distant future, and I'm saying: You can't brief her! You can't brief her," Trump said. "Let's protest."

Trump also continued to call for restrictions on immigrants from countries with high rates of terrorism, and he listed examples of refugees, immigrants or student visa holders who arrived in the United States and then attacked Americans. Some of the countries he mentioned: Syria, Yemen, Uzbekistan, Iraq, Somalia, Morocco and the Philippines.

"Hillary Clinton wants to have them come in by the hundreds of thousands — just remember," Trump said. "This has nothing to do with politics, folks. This is a whole different level. This has to do with pure, raw stupidity. Okay?"

Trump was repeatedly interrupted by protesters on Thursday afternoon, including several who held up pocket Constitutions, a tribute to Khizr Khan, a Muslim lawyer from Virginia whose son was killed in Iraq in 2004. He spoke at the Democratic National Convention last month, accusing Trump of having not read the Constitution and offering to share his pocket-size copy. Since then, Trump and Khan have engaged in a highly public feud.

Richard Oliver, 44, a Trump supporter from Waterboro who attended the Thursday rally, said he doesn't think Trump made a mistake when criticized Khan and his wife. He said he doesn't see why the Khans deserve so much attention.

"I don't see why they are so special," he said as he left the auditorium after Trump finished speaking. "There are other American-born soldiers who have fought and died for their country."

Kathleen McIntyre, 54, of Westbrook, interjected and said that Khan is "just a plant for the Clinton machine."

In a city square a few blocks from the auditorium, more than 50 people staged a protest. The group, mostly members of Portland's legal community, had taken a half-page ad in the Portland Press Herald asking people to “Stand up for Maine values.” About 100 other protesters gathered outside City Hall and chanted “love trumps hate” and sang, “This Land Is Your Land.”

Emma Woodhead, 18, held a sign that said: “Always Stay Humble and Kind," a phrase taken from the title of a Tim McGraw country song.

“It’s just the opposite of what Trump is,” she said.

Trump supporter Chad Johnson, 49, who voted for Sen. Bernie Sanders, a Democratic contender, in the Maine caucuses, said he's "frustrated" with the mistakes Trump has made in the past week, notably his unwillingness to endorse House Speaker Paul D. Ryan (R-Wis.).

"There is no party unity," said Johnson, a Portland Republican. "That was upsetting to me and for a lot of people."

While his enthusiasm for the Republican nominee has weakened in the past week, he said, he will still vote for Trump because he is so angry at Clinton and the Democratic Party for playing "dirty tricks" to stop the Sanders campaign.

Arthur Sheppard, a Trump supporter who works as a bouncer at Portland nightclub, said he is willing to overlook Trump's mistakes because he said they reflect his lack of political experience. He said he likes Trump because he's an outsider.

"At the end of the day, he's not a politician," Sheppard said. "He doesn't bow to the establishment and the powers that be. He carves his own path."

Tom Aldred, 62, retired landscaper, said he forgives Trump for his mistakes because they are political gaffes rather than real-world misjudgments.

“We all make mistakes,” said Aldred, a Portland independent. “I can overlook his novelty. I think he is sincere and loves his country.”

Johnson reported from Washington.