Trump has long incorrectly suggested his Democratic opponent wants to overturn the Second Amendment and take away Americans' right to own guns. At a rally in Miami, he again riffed about confiscating the agents' guns and then went further.
"I think that her bodyguards should drop all weapons. They should disarm, right?" Trump asked the crowd. "Take their guns away, she doesn't want guns. Take their — and let's see what happens to her. Take their guns away. OK, it would be very dangerous."
Trump's meaning was not immediately clear and a campaign spokeswoman did not immediately respond to a request for an elaboration.
But the Clinton campaign had a quick reaction. Spokesman Robby Mook released a statement Friday night saying Trump "has a pattern of inciting people to violence. Whether this is done to provoke protesters at a rally or casually or even as a joke, it is an unacceptable quality in anyone seeking the job of Commander in Chief.
"This kind of talk should be out of bounds for a presidential candidate," Mook wrote.
A spokeswoman for the Secret Service declined to comment.
The seemingly ominous comment evoked a remark Trump made last month that many Democrats condemned as a call for Clinton's assassination. Speaking at a rally in North Carolina, the Republican nominee erroneously said his opponent wants to "abolish, essentially, the Second Amendment."
He continued: "By the way, if she gets to pick her judges, nothing you can do, folks. Although the Second Amendment people, maybe there is, I don't know."
Within minutes, the Clinton campaign condemned the remark. Mook said then, "A person seeking to be the president of the United States should not suggest violence in any way."
Trump later disputed that criticism, saying everyone in his audience knew he was referring to the power of voters and "there can be no other interpretation."
Trump, who has the endorsement of the National Rifle Association, eventually took to Twitter to say the Secret Service had not contacted him about the remarks.
The comments Friday in Miami came hours after Trump finally reversed his long-held position that President Barack Obama was not born in the United States. Appearing in Washington, he said Obama was born in the United States but then incorrectly suggested that the Clinton campaign had started the conspiracy theory.
Trump ignored questions from reporters about his switch and has yet to explain why he abandoned the "birther" stance that fueled his political fame and was viewed by critics as an attempt to delegitimize the nation's first African-American president.
While campaigning in South Florida, which has a large Cuban-American population, Trump also said that if he's elected president, he will reverse Obama's efforts to normalize relations with Cuba — unless the country abides by certain "demands." Among those, he said, would be religious and political freedom for the Cuban people and the freeing of all political prisoners.
Trump says he'll "stand with the Cuban people in their fight against communist oppression."
The comment marks yet another reversal for the GOP candidate, who previously said he supported the idea of normalized relations, but wished the U.S. had negotiated a better deal.
Trump also said the U.S. has a broader obligation to stand with oppressed people — a comment that seems at odds with his "America first" mantra. "The next president of the United States must stand in solidarity with all people oppressed in our hemisphere, and we will stand with oppressed people, and there are many," he said.
He added that the people of Venezuela "are yearning to be free, they are yearning for help. The system is bad. But the people are great."
Trump has often cited the country as a model of a failed state, warning that if Clinton is elected, she'll turn the U.S. into Venezuela.