FBI agents recovered a stack of folders labelled “Trump I-IV” during a raid on John Bolton, the president’s former national security adviser.

Mr Bolton’s Maryland home was searched last month as part of an investigation into potential unauthorised retention or removal of classified documents.

A search warrant application cites possible violations of two laws, including the Espionage Act, which makes it a crime to collect or share national defence information without permission.

Alongside “typed documents in folders labelled ‘Trump I-IV’”, investigators recovered two computers, two mobile phones, a laptop, several digital storage drives and a binder labelled “statements and reflections to Allied Strikes”, according to the search warrant obtained from Maryland district court.

The court documents were unsealed by a federal judge after a group of news organisations argued it was in the public interest for them to be released.

Critics initially cast the raid as an act of retribution by Donald Trump against his highly critical former aide, but reports have since claimed the investigation into Mr Bolton began under the Biden administration.