The deepening investigation into Trump's handling of sensitive government information has disclosed damaging and unsettling new details. With every court filing there is new information about the cache of documents the former president took with him from the White House and the potential national security concerns.

While the unprecedented search has galvanised many Republicans to Trump's defence, others in the party are unwilling to speak up, often wary of crossing him.

Senate Republican leader Mitch McConnell declined to respond on Wednesday when asked about the latest developments in the Justice Department's probe.

"I don't have any observations about that," he told reporters in Kentucky.

The silence speaks volumes for a party whose president won the White House after rousing voters in rally chants of "Lock Her Up!" Trump pilloried Democratic opponent Hillary Clinton for using a personal email account and server during her time as Secretary of State. She quickly complied with investigators and was not charged.

The investigation also is posing a new test of Republican loyalty to Trump from lawmakers who are relying on him for their political livelihoods, particularly ahead of the midterm elections.

Battle lines among Republicans infighting over Trump quickly emerged Wednesday after the latest court filing, in which Justice Department said that the FBI's August 8 search had produced more than 100 documents with "classified markings" at Mar-a-Lago -- twice as many as Trump's team had turned over earlier this summer.

In Tuesday's late filing, the Justice Department laid out in stark detail how it had developed evidence "that government records were likely concealed and removed" from a storage room at Trump's Mar-a-Lago.

The filing described the lengthy process of trying to retrieve government documents taken when Trump left the White House in early 2021. The Justice Department explained how Trump's legal team had said documents were only been kept in the storage room, but the search also found documents in the former president's office. It said some of the newly found documents were so sensitive that even Justice Department lawyers and FBI counterintelligence personnel required additional clearances before they could review the material.

The Justice Department said "efforts were likely taken to obstruct the government's investigation." It produced a photograph of some of the classified documents found, as evidence. The filing said flatly that the government believes "obstructive conduct" has occurred.

Republican Liz Cheney -- one of the former president's fiercest critics, who recently lost her own primary for re-election -- tweeted the photo: "Yet more indefensible conduct by Donald Trump revealed this morning."

But Republican Ted Cruz, once a rival to Trump for the White House, has saved his criticising for federal law enforcement as he defended the former president.

"The FBI's raid was a horrific 'abuse of power,'" Cruz tweeted just before the Tuesday filing. He said "there needs to be 'a complete housecleaning' at FBI".

He was among several Republican lawmakers and congressional candidates who were fundraising this week off their complaints about the Justice Department. Cruz's office did not respond to a request for fresh comments Wednesday.

In the immediate aftermath of the search, Republicans largely rallied around Trump and demanded more information from the Justice Department. House and Senate Republicans, and some Democrats, sought hearings and briefings.

But as new information emerges, including the court's release last week of the federal affidavit supporting the search and Tuesday's Justice Department filing, it may make it more difficult for Trump's allies to defend the former president and his team's actions.

Senate Republicans are growing concerned that Trump is stealing the focus away from what they would prefer to be an election referendum on President Joe Biden's performance in the White House.

Australian Associated Press