A US judge on Friday made public more evidence collected by prosecutors in the federal criminal case accusing former president Donald Trump of attempting to overturn his defeat in the 2020 election.

The hundreds of pages, many of which were blanked out and marked "sealed," include material referenced in a sweeping court filing from Special Counsel Jack Smith. The filings made public earlier this month argued that Trump, the Republican presidential candidate in this year's election, is not immune from the remaining allegations in the case.

The filings unsealed on Friday included excerpts of interviews conducted by Congress's official probe into the Jan 6, 2021, assault on the US Capitol by Trump's supporters.

Witness names were blacked out, but some could be identified by matching them up with other known events. For instance, former Attorney General William Barr describes being summoned to the White House after an interview in which he said the election had not been marred by large-scale fraud, and expecting to be fired.

A few days after that interview, Trump announced on social media that Barr had stepped down.

Smith’s court filing contained few details that had not already been made public, but provided a detailed account of Trump’s efforts to hold onto power following his election loss, including descriptions of Trump’s conversations with family members and aides.

A compilation of the evidence was submitted as an attachment to Smith’s filing, but its public release was delayed to give the former president time to raise objections.

Much of the evidence, including reports of witness interviews, transcripts of grand jury testimony and records obtained through search warrants, has been redacted in the public release.

Trump’s lawyers argued that none of the material should be released ahead of the Nov 5 election and successfully delayed its publication by a week. His defence team ultimately chose not to appeal US District Judge Tanya Chutkan’s decision to release redacted versions of the documents.

Trump has pleaded not guilty to four criminal charges accusing him of a multipart conspiracy to obstruct the process to collect and certify the results of his 2020 defeat to Democrat Joe Biden.

The case has been slowed by a US Supreme Court ruling that former presidents have broad immunity for official actions taken while in office. It will not go to trial before the election, when Trump faces Democratic Vice President Kamala Harris.

Trump has argued the entire case should be thrown out based on the Supreme Court's decision. Should Trump win in November, experts believe he will order the US Department of Justice to drop the case.