The FBI has found an additional classified document in a search of former US Vice-President Mike Pence's home in Indiana.
It follows disclosures by his attorneys that they found "a small number" of classified files from his vice-presidency at the home last month.
An adviser for Mr Pence confirmed that additional files were removed following "a thorough and unrestricted search".
Mr Pence agreed to the consensual search, he added.
"The Department of Justice completed a thorough and unrestricted search of five hours and removed one document with classified markings and six additional pages without such markings that were not discovered in the initial review by the vice-president's counsel," said adviser Devin O'Malley in a statement on Friday.
The search was conducted by FBI agents from Indianapolis and is not currently linked to other investigations into classified files, CBS, the BBC's US partner, reported.
It is the latest development in a growing controversy over classified documents that has already embroiled both former President Donald Trump and incumbent President Joe Biden.
Mr Trump faces a criminal investigation for allegedly mishandling classified documents, while Mr Biden faces a probe by the US Department of Justice.
A spokesperson for Mr Pence told CNN he was away, though a private attorney was present at the house.
In January, representatives for Mr Pence sent a letter to the National Archives - the US government agency that manages the preservation of presidential records - alerting them that they had found classified documents in the former vice-president's home.
Those materials have already been handed over to the FBI.
Classified records are supposed to go to the National Archives once an administration leaves office.
The documents were "inadvertently boxed and transported" to Mr Pence's home at the end of the Trump presidency, an attorney for Mr Pence has said.
A simple guide to the US classified documents saga
The documents were found after Mr Pence sought legal help from specialists in handling classified documents "out of an abundance of caution", following the discovery of classified files at Mr Biden's Delaware home and his private Washington DC office.
The FBI search of Mr Pence's residence comes after a search of Mr Biden's home in Rehoboth Beach, Delaware, on 1 February.
No additional classified files were found in the nearly four-hour search of that property, lawyers for the president have said.
Mr Biden has said that his team did "what they should have done" by alerting officials immediately when classified files were found and that he is co-operating with the special counsel's investigation.
The FBI did not need to obtain a warrant for searches of Mr Biden's property, as his lawyers had agreed to the probe.
The federal agency did, however, obtain a warrant for their search of Mr Trump's Mar-a-Lago residence in Florida last year for classified documents.
To date, about 300 classified documents have been recovered from Mr Trump since his administration ended.
The search warrant came after attorneys representing Mr Trump had said all government records had been returned.
Mr Trump has repeatedly denied any wrongdoing and claimed that he declassified any documents he took when he left the White House.
Mr Pence was recently issued a legal summons to testify in the investigation into Mr Trump. Sources have said the subpoena is related to the ex-president's bid to overturn his 2020 election defeat.
bbc.news
