“I need to open with a very critical breaking news announcement,” said Trump. “The FBI has just sent a letter to Congress informing them that they have discovered new emails pertaining to the former Secretary of State Hillary Clinton’s investigation.”
Continuing over a roar of cheers, Trump added, “And they are reopening the case into her criminal and illegal conduct that threatens the security of the United States of America.”
Trump joked with the crowd that nothing else he would say could top the news and then questioned whether he should even continue.
"With that being said, the rest of my speech is going to be so boring," he said. "Should I even make this speech?”
In the letter, FBI director James Comey writes that “in connection with an unrelated case, the FBI has learned of the existence of emails that appear to be pertinent to the investigation [of Clinton’s personal email server.]”
Comey added that the FBI would “take appropriate investigative steps designed to allow investigators to review these emails to determine whether they contain classified information, as well as to assess their importance to our investigation.”
In July, after concluding their investigation, Comey announced that the bureau would not be recommending charges against Clinton. He later defended the decision in a politically-divided appearance before the House Oversight and Government Reform Committee.
Trump has sought to make Clinton’s handling of classified information as secretary of state a campaign issue throughout the year, often questioning at campaign rallies how she avoided charges.
“In all fairness for all of the people that have suffered for doing so much less… perhaps finally justice will be done,” said Trump.
Trump has been critical of the FBI, speculating that the lack of charges represented corruption at the highest levels. In an interview with ABC News’ Chief Anchor, George Stephanopoulos, Trump said of Comey, "he made a mistake. OK?... I don't even call it a mistake. I think something happened."
But today, the Republican nominee shifted his tone, applauding the decision to examine further emails and scrutinize the original investigation.
“I have great respect for the fact that the FBI and the Department of Justice are now willing to have the courage to right the horrible mistake that they made,” said Trump. “This was a grave miscarriage of justice that the American people fully understood. And it is everybody's hope that it is about to be corrected.”
The announcement from the FBI even led Trump to make a major reversal, musing that perhaps the election was not rigged after all, an idea that Trump has been perpetuating for months, even after election officials have said that there was no evidence of widespread voter fraud or voting malpractice.
“It might not be as rigged as I thought, right?” said Trump. “The FBI, I think they are going to right the ship, folks. I think they are going to right the ship.”
Clinton was on her campaign plane headed to Iowa when the news broke, but there was no internet available on board so no one knew about the announcement until a reporter briefly received service. Clinton spokesman Nick Merrill appeared surprised when asked about the letter.
As of Trump's rally, neither Clinton nor her campaign has commented on the news. One top aide told ABC News that he was learning about everything in real time upon landing in Iowa.
ABC News' Cecilia Vega contributed to this report.