AP Greenbelt (US)

John Bolton, who served as national security adviser to US President Donald Trump during his first term and later became a vocal critic of the Republican leader, was charged on Thursday with storing top secret records at home and sharing with relatives diary-like notes about his time in government that contained classified information.

The 18-count indictment also suggests classified information was exposed when operatives believed to be linked to the Iranian regime hacked Bolton's email account and gained access to sensitive material he had shared. A Bolton representative told the FBI in 2021 that his emails had been hacked, prosecutors say, but did not reveal he had shared classified information through the account or that the hackers now had possession of government secrets.

The indictment sets the stage for a closely-watched court case centring on a longtime fixture in Republican foreign policy circles who became known for his hawkish views on American power and who served for more than a year in Trump's first administration before being fired in 2019 and publishing a scathingly-critical book about the president.

The case, the third against a Trump adversary in the last month, will also unfold against the backdrop of concerns that the Justice Department is pursuing the president's political enemies while at the same time, sparing his allies from scrutiny. Bolton foreshadowed that argument in a defiant statement on Thursday in which he denied the charges and called them part of an "intensive effort" by Trump to "intimidate his opponents".

"Now, I have become the latest target in weaponising the Justice Department to charge those he deems to be his enemies with charges that were declined before or distort the facts," he said.

Even so, the indictment is significantly more detailed in its allegations than earlier cases against former FBI Director James Comey and New York Attorney General Letitia James. Unlike the other two cases filed over the last month by a hastily-appointed US attorney, this one was signed by career national security prosecutors.