WASHINGTON (AP) — The FBI has arrested a suspect five years after an unidentified person placed two pipe bombs outside the headquarters of the Republican and Democratic national parties in Washington.

Agents arrested Brian J. Cole Jr., 30, of Woodbridge, Virginia, on explosive charges. Calls to relatives of Cole listed in public records were not immediately returned.

The mystery behind the person’s identity has baffled law enforcement and fueled conspiracy theories about Jan. 6, 2021, and the Capitol riot by a mob of President Donald Trump’s supporters.

Authorities have not disclosed what led them to Cole, but the arrest follows a renewed examination of evidence and data. Attorney General Pam Bondi emphasized that diligent investigative work was key in discovering Cole's identity.

The investigation into the bombings drew from various tools, including credit card purchases linked to the materials used, and cellphone data that ultimately pointed to Cole.

Past efforts to identify the suspect had yielded little to no information, leaving investigators with many unanswered questions regarding the individual's motives and the connection between the bombings and the riot at the Capitol the following day.

Authorities reported that Cole had made credit purchases in 2019 and 2020 for items consistent with those used in bomb-making, which included galvanized pipes and kitchen timers. Surveillance video captured a figure wearing distinct clothing during the time of the incident.

Despite his arrest, the motives behind Cole's actions and any potential links to the Capitol assault remain unclear, exacerbated by the lack of any clear history of criminal behavior or political affiliation from the suspect.

As far as community insight goes, former classmates describe Cole as quiet and friendly, raising further questions about his motivation and actions preceding the incident. The investigation remains ongoing as more details unfold.