John Bolton, who served as Donald Trump's national security adviser before becoming a vocal critic of the president, has been criminally indicted on federal charges.

The Department of Justice presented a case to a grand jury in Maryland on Thursday, which resulted in Bolton's indictment as they found sufficient evidence. Bolton, 76, issued a statement maintaining his innocence amid the charges.

This indictment comes after FBI agents conducted a search of Bolton's home and office earlier in August, as part of an investigation into his handling of classified information.

Bolton is now the third political opponent of Donald Trump to face legal challenges in recent weeks. The charges could result in decades of prison time if Bolton is convicted.

The indictment, which spans 26 pages, details eight counts of transmission of national defense information and ten counts of unlawful retention. Prosecutors allege he transmitted classified national defense information using personal email and messaging apps.

Documents specified in the indictment reportedly revealed sensitive intelligence about potential foreign threats and U.S. foreign relations.

Bolton could face 10 years in prison for each charge, and he is anticipated to surrender to authorities shortly. In his defense, he has accused the Trump administration of weaponizing the Justice Department against him, while his lawyer defended his extensive record-keeping as harmless and properly shared.

In light of this personalization of justice, Bolton referenced his record of public service, asserting that his alleged 'diary-like' entries have been misconstrued as criminal behavior.

Bolton's case reflects ongoing political turmoil, where the former national security adviser becomes a target within a broader context of criminal charges filed against various critics of Trump in the political arena.