During interviews with the FBI, the 30-year-old confessed to planting the explosive devices near the Democratic and Republican party headquarters, three sources told NBC News.

A surveillance photo released by the FBI shows a person of interest in Washington, D.C., on Jan. 6, 2021. FBI via Reuters

The man charged with planting two pipe bombs near the Democratic and Republican party headquarters on the eve of the Jan. 6 attack on the U.S. Capitol told the FBI he believed conspiracy theories about the 2020 election, according to two people familiar with the matter.

Brian Cole Jr., 30, is cooperating with the FBI, NBC News has reported, citing a separate person familiar with the matter. Cole appeared in court Friday, one day after he was charged with leaving pipe bombs outside the Republican National Committee and Democratic National Committee in the hours before Donald Trump supporters stormed the U.S. Capitol. Trump has falsely claimed the 2020 election was "rigged."

Cole confessed to planting the devices outside the parties` headquarters in the hours before the Capitol attack, three people familiar with the matter told NBC News. A federal prosecutor said in court on Friday that the suspect spoke with the government for more than four hours, but did not reveal the contents of those discussions.

Cole was charged with transporting an explosive device and attempted malicious destruction by means of explosive materials, according to charging documents. The FBI has not publicly cited a motive.

In court Friday in a prison jumpsuit, Cole vowed to answer all questions asked honestly and told the judge he graduated from high school and hadn`t had any alcohol or drugs that would impact his ability to understand what was happening.

He added that he did not need a court-appointed attorney and hired his own. His attorney, John Shoreman, did not immediately return a request for comment.

The pipe bombs he`s accused of planting were found the day of the Jan. 6 riot, though investigators have said they were placed near the RNC and DNC on Jan. 5.

Trump received about 74 million votes nationally in 2020, while Joe Biden received roughly 81 million.

Trump`s claims about the 2020 election were part of former Special Counsel Jack Smith`s investigation into his efforts to overturn the results. In his final report on the investigation, Smith said that Trump "inspired his supporters to commit acts of physical violence" by spreading "demonstrably and, in many cases, obviously false" claims about the 2020 election. Trump has publicly maintained that he believed he won the election.

The criminal case against Trump in connection with the Jan. 6 attack was dropped after he was elected in 2024, but Smith said that "but for Mr. Trump`s election and imminent return to the Presidency, the Office assessed that the admissible evidence was sufficient to obtain and sustain a conviction at trial."

Smith recently said he wanted to publicly testify about his investigation, but House Republicans rejected his request, instead planning to interview him behind closed doors on Dec. 17.