John Bolton, who served as national security adviser during Donald Trump's first term before becoming a critic of the president, pleaded not guilty on Friday to charges of mishandling classified information.

A federal grand jury in Maryland charged Bolton Thursday with eight counts of transmission of national defense information and 10 counts of unlawful retention of that information. He faces up to 10 years in prison, a $250,000 fine per count, and three years of special release.

Prosecutors allege that the former national security adviser transmitted national defense information using his personal email or a messaging application to send sensitive documents classified as Top Secret. The documents allegedly revealed intelligence about future attacks, foreign adversaries and foreign-policy relations.

The Justice Department also alleged that Bolton illegally retained documents containing national defense information within his home. These documents included intelligence on an adversary's leaders as well as information revealing sources and collections used to obtain statements on a foreign adversary.

Bolton denied any wrongdoing in a statement on Thursday and said the charges were politically motivated. He said Trump sought "retribution" against him during his first term in the White House and continued after he tried to block publication of Bolton's book before the 2020 election.

"Now, I have become the latest target in weaponizing the Justice Department to charge those he deems to be his enemies with charges that were declined before or distort the facts," Bolton said. He added that the charges are about Trump's "intensive effort to intimidate his opponents, to ensure that he alone determines what is said about his conduct."

Bolton's lawyer, Abbe Lowell, said in a statement Thursday that his client didn't break the law.

"The underlying facts in this case were investigated and resolved years ago," Lowell said. "These charges stem from portions of Amb. Bolton's personal diaries over his 45-year career — records that are unclassified, shared only with his immediate family, and known to the FBI as far back as 2021."

Bolton is the third critic of the president to face an indictment since the end of September. The Justice Department also brought charges against New York Attorney General Letitia James, who led the civil case against Trump and his businesses, and former FBI Director James Comey, who clashed with Trump during the president's first term.