The Democratic chair of the US Senate intelligence committee has demanded that a federal judge allows the committee to be briefed on the FBI’s search of Mar-a-Lago and the potential damage caused by Donald Trump hoarding top secret documents at his private club.

Mark Warner, the US senator from Virginia, said that there was confusion over whether the Department of Justice (DoJ) and the FBI were allowed to brief the Senate committee on their review of classified documents held at the former president’s club-resort and residence in Palm Beach, Florida.

The FBI searched the property on 8 August, retrieving more than 100 classified documents.

Last week a Trump-appointed judge, Aileen Cannon of the federal district court for thesouthern district of Florida, sided with Trump and ordered a “special master” to oversee the documents. The DoJ is appealing the decision, but its criminal investigation of Trump’s removal of state secrets from the White House has been halted by the court’s action.

Warner told CNN’s State of the Union on Sunday that clarification from the judge was urgently needed, and the mishandling of state secrets could have disastrous consequences.

“Some of the documents involved human intelligence, and if that information got out people will die. If there were penetration of our signals intelligence, literally years of work could be destroyed.”

Warner added that if information in the documents had been obtained from foreign intelligence services, then “the willingness of our allies to share intelligence could be undermined”.

Hillary Clinton, the former presidential candidate who lost to Trump in 2016, argued that he should be liable to criminal prosecution. She told CNN on Sunday: “No one is above the law, no one should escape accountability … He is not the president and so I do think, just like any American, if there is any evidence that should be pursued.”

The White House has stayed aloof from the DoJ’s actions..

US vice-president Kamala Harris declined to answer in an NBC interview whether Trump’s status as a possible presidential candidate in 2024 should be taken into account in the DoJ’s criminal investigation.

“I wouldn’t dare tell the Department of Justice what to do,” she said. “The president and our administration, unlike the previous administration, have been very, very careful to make sure there is no question about any kind of interference.”

Pressed on whether it would be too divisive to prosecute a former president, Harris signaled that Trump should be held accountable, saying: “Our country has gone through different periods of time where the unthinkable has happened, and where there has been a call for justice, and justice has been served…people are going to demand justice, and they rightly do.”