Republicans continued to defend former President Donald J. Trump on Sunday, despite an unprecedented F.B.I. search of his Florida home, revealing deep cracks in the party’s support for law enforcement amid a federal investigation into Mr. Trump’s handling of top secret documents.

Immediately following the search, congressional Republicans, including members of the leadership, reacted angrily, launching attacks on the nation’s top law enforcement agencies. Some called for the FBI to be “defunded” or “destroyed,” while others compared it to the Nazi secret police, using terms like “gestapo” and “tyrants.”

On Sunday, more moderate members of the party chastised their colleagues for their anti-law enforcement rhetoric, arguing for defending Mr. Trump while also overseeing the Justice Department.

Many Republicans demanded the release of the affidavit supporting the search warrant executed last Monday, which would detail the evidence that convinced a judge there was probable cause to believe a search would turn up evidence of crimes. Typically, such documents are not made public before charges are filed.

Threats against law enforcement prompted the calls for a more cautious tone. After a gunman opened fire on an F.B.I. office in Cincinnati on Thursday, the Department of Homeland Security issued an intelligence bulletin to law enforcement across the country warning of “an increase in threats and acts of violence, including armed encounters, against law enforcement, judiciary, and government personnel” following the search.

Another gunman rammed a car into a barricade outside the Capitol around 4 a.m. on Sunday, heightening the tension. He shot into the air several times before killing himself after exiting the burning car, according to Capitol Police.

On Friday, a federal judge unveiled the search warrant and an inventory of items taken from the property by federal agents. According to the list, the FBI retrieved 11 sets of classified documents as part of an investigation into potential violations of the Espionage Act and two other laws.

Mr. Trump and his supporters have claimed that former President Barack Obama also mishandled the situation, claiming that the judge who signed the warrant authorizing the search was biased, that the F.B.I. may have planted evidence, that the documents were protected by attorney-client or executive privilege, and that Mr. Trump had declassified them.

Senator Rand Paul, a Republican from Kentucky, called for the repeal of the Espionage Act, one of the statutes that prompted the investigation, on Saturday.

However, the shifting explanations have made it difficult for Republicans, many of whom are eager to please the former president, to mount a united defense. They disagree on whether to target the nation’s top law enforcement agencies and how aggressive to be in those attacks.

Representative Marjorie Taylor Greene, a Georgia Republican featured in fund-raising appeals by the National Republican Congressional Committee, has begun selling merchandise with the slogan “Defund the F.B.I.”

However, two of the laws mentioned in the search warrant make taking or concealing government records a crime, regardless of whether they are related to national security. The third provision, which prohibits the unauthorized retention of material containing restricted national security information, applies regardless of whether the material is classified.

Republican Senate and House leaders, Senator Mitch McConnell of Kentucky and Representative Kevin McCarthy of California, have both stated that Mr. Garland must provide answers.

Mr. Garland, for his part, held a press conference on Thursday to defend the Justice Department’s handling of the case.

To avoid the appearance of partisanship, the White House has been reluctant to comment on the investigation. “We don’t get involved.” “We don’t get briefed,” White House press secretary Karine Jean-Pierre said on ABC’s “This Week,” adding, “We’re going to let Merrick Garland speak for himself and his department.”

Senator Rob Portman of Ohio, the top Republican on the Homeland Security Committee, has requested that Mr. Garland’s actions be investigated.

“Never before has a former president and potential political opponent to the sitting president faced such a search,” Mr. Portman said in a statement. “The attorney general and the F.B.I. should now demonstrate unprecedented transparency and explain to the American people why they authorized the raid.”