US Vice President Kamala Harris has accused Republican leaders of making "dangerous" attacks on the FBI over the raid at Donald Trump's Mar-a-Lago estate.
A number of GOP senators have alleged that the raid was politically motivated.
Her comments came after a search warrant released by a court showed 11 sets of classified documents were removed by agents from Trump's Florida home.
The warrant was granted after the FBI showed the probable cause of potential violations of the Espionage Act.
Trump has called the raid a "witch hunt" and suggested that the FBI might "plant" evidence, and other leading Republicans have rallied to his defence.
But Harris said: "As a former prosecutor, I will tell you, I don't speak about anybody else's case, but I have full confidence that the Department of Justice will do what the facts and the law requires.
"And any so-called leader who engages in rhetoric that in any way suggests that law enforcement should be exposed to that kind of danger is irresponsible and results in dangerous activities."
She added: "I think it's just highly irresponsible of anyone who calls themselves a leader and certainly anyone who represents the United States of America to engage in rhetoric for the sake of some political objective that can result in harm to law enforcement officers and agents."
Three days after the FBI raid, a man attacked the agency's field office in Cincinnati, Ohio brandishing an assault rifle and nail gun.
He then fled and, following a chase, was shot dead by police.
It emerged late on Friday that the gunman, Ricky Walter Shiffer Jr, 42, was a veteran of the US Navy and Florida National Guard.
He had served as a fire control technician on the nuclear-powered submarine USS Columbia.
That meant at one point he himself would have had "top secret" security clearance.
He was already under investigation in connection to the Jan 6, 2021 riot at the US Capitol, the Wall Street Journal reported.
The gunman had posted on Trump's social network Truth Social before attacking the FBI.
Schiffer wrote: "People this is it. I hope a call to arms comes from someone better qualified, but if not, this is your call to arms from me."
After his attempt to storm the FBI office failed, he wrote: "Well, I thought I had a way through bulletproof glass, and I didn't."
The records seized from Mar-a-Lago include some marked "sensitive compartmented information", a special category above "top secret" that is meant to protect the most important US secrets.
The classification is given to documents that, if revealed publicly, could cause "exceptionally grave" damage to US interests.
There were no details in the warrant about what specific information the documents might contain.
Trump has rejected as a "hoax" reports that there may have been documents relating to nuclear programmes.
According to the warrant, the FBI was investigating potential violations of three different laws.
That included one that governs gathering, transmitting or losing defence information under the Espionage Act.
The other laws involved the concealment, mutilation or removal of records and the destruction, alteration or falsification of records.
A property receipt that was released by the court in Florida showed documents taken away by the FBI also included a presidential order made by Trump pardoning his friend Roger Stone.
There was also a "leather-bound box of documents", information about the "president of France", a binder of photos, a handwritten note, and "miscellaneous secret documents".
Trump said the documents seized by agents had all already been "declassified", and that he would have turned them over if the Justice Department had asked him to.
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