A Virginia man has been arrested in connection with two pipe bombs placed outside the headquarters of the Republican and Democratic national committees on the eve of the 2021 Capitol riot.

US Attorney General Pam Bondi said Brian Cole Jr., 30, was arrested without incident early on Thursday morning. He is charged with use of an explosive device and attempted malicious destruction by means of explosive materials.

Officials did not specify a possible motive for the planting of the pipe bombs, which were safely deactivated without exploding.

It caps an exhaustive investigation in a case where an arrest had eluded law enforcement despite a $500,000 (£375,000) reward.

The FBI did not receive new information or a tip that cracked the case, officials said.

Both bombs were placed on the night of 5 January 2021 and were only discovered the following afternoon as supporters of Donald Trump stormed the US Capitol in the last days of his first presidency.

Kamala Harris, who was the US vice president-elect at the time, was evacuated from the Democratic National Committee headquarters shortly after the devices were found.

According to court documents, the suspect lives with his parents in Woodbridge, a suburb about 20 miles (32km) outside Washington.

He works for a bail bond company - such firms help people get out of jail by posting bail on their behalf in exchange for a non-refundable fee.

Investigators sifted through a mountain of evidence gathered over the years, including some three million lines of data.

Mr. Cole allegedly bought multiple bomb-making components in 2019 and 2020, according to the court filing.

He purchased metal end caps, wires, and steel wool at Home Depot and Lowes hardware stores, batteries at another retailer, and timers at a Walmart in northern Virginia, an FBI affidavit states.

Investigators found mobile phone data that showed Mr. Cole was near the locations of the pipe bombs when they were planted between 19:39 and 20:24 local time on 5 January 2021.

His car - a 2017 Nissan Sentra with a Virginia license plate - was also seen by a license plate reader less than half a mile (0.8km) from the location where the individual who placed the devices was first observed in the area.

US Attorney Jeanine Pirro told a news conference on Thursday that the Trump administration had made solving the case a priority.

FBI officials praised the perseverance of agents and said they never gave up on finding a suspect.

The case remains a stark reminder of the violence that took place on January 6, 2021, and the vulnerabilities that were exposed on that fateful day.