Federal authorities on Thursday arrested a 30-year-old Virginia man in connection with the pipe bombs placed outside the headquarters of the Democratic National Committee and Republican National Committee on the eve of the January 6, 2021, Capitol riot.

Brian Cole Jr. of Woodbridge, Virginia, was taken into custody early Thursday morning and charged with transporting an explosive device and attempted malicious destruction by means of explosive materials. The arrest comes nearly five years after the devices were planted and marks the first arrest in what had been one of the FBI's most high-profile unsolved cases.

Attorney General Pam Bondi announced the arrest during a news conference at the Department of Justice. She said the investigation is ongoing and additional charges could be filed.

"Early this morning, Brian Cole Jr. was arrested and charged with placing the pipe bombs at the RNC and the DNC on January 5, 2021," Bondi said. "As we speak, search warrants are being executed and there could be more charges to come."

The investigation breakthrough

Bondi said no new tips or witnesses led to the arrest. Instead, investigators identified Cole by re-examining evidence that had already been collected.

"Let me be clear: There was no new tip. There was no new witness. Just good diligent police work and prosecutorial work," Bondi said.

According to an FBI affidavit filed Wednesday in U.S. District Court in Washington, investigators tied Cole to the bombs through purchase records, cell phone data and license plate reader information.

The document states that Cole purchased multiple items in 2019 and 2020 consistent with the components used to manufacture the two devices at Home Depot, Walmart, Lowe's and Micro Center stores in northern Virginia. The purchases included six galvanized pipes, black and galvanized end caps, 9-volt batteries, Walmart kitchen timers, electrical wire, steel wool and battery connectors.

The FBI also connected Cole to the incident through cellphone tower data. According to the affidavit, his phone engaged in approximately seven data sessions with cell towers in the area of the RNC and DNC between 7:39 p.m. and 8:24 p.m. on January 5, 2021.

A license plate reader captured Cole's 2017 Nissan Sentra driving past the South Capitol Street exit from Interstate 395 South, less than half a mile from where the individual who placed the devices was first observed on foot.

U.S. Attorney for the District of Columbia Jeanine Pirro described identifying the suspect as finding "a needle in a haystack."

"This case involved millions of pieces of data," Pirro said. Investigators examined 233,000 purchases of black end caps of the type used in the devices, she noted.

What Cole told investigators

Cole spoke with FBI investigators for more than four hours following his arrest, according to the Justice Department. During those interviews, Cole told agents he believed the 2020 election was stolen from President Donald Trump, according to people briefed on the matter who spoke to multiple news outlets.

Pirro said in an interview with ABC News that Cole expressed disappointment in "both sides of the system."

"He was disappointed in various aspects of the election, but this guy was an equal opportunity bomber," Pirro said. "He put a bomb outside the Republican National Committee and the Democrat National Committee."

Two people briefed on the arrest told NBC News that Cole has been linked to statements showing support for an anarchist ideology. Bondi declined to comment on Cole's motivations during Thursday's news conference, saying the investigation remains ongoing.

Details of the devices

The pipe bombs were planted on the evening of January 5, 2021, hours before supporters of President Trump stormed the Capitol as Congress met to certify the 2020 election results. The devices were not discovered until approximately 1 p.m. the following day, roughly 15 hours after they were placed.

According to the FBI, the bombs were made from one-by-eight-inch pipes, kitchen timers and homemade black powder. The bureau has said both devices were viable and could have killed or injured people in the vicinity.

Vice President-elect Kamala Harris was inside the DNC headquarters when the device there was discovered. She was evacuated from the building by her Secret Service detail.

The discovery of the bombs diverted law enforcement resources from the Capitol at a critical time as the riot unfolded nearby.

Profile of the suspect

Cole is described in court documents as 5 feet 6 inches tall and wearing corrective eyeglasses. Surveillance footage released by the FBI over the years showed the suspected bomber was approximately 5 feet 7 inches tall, wearing a face mask, glasses, a gray hooded sweatshirt and gloves, with a dark backpack slung over one shoulder.

According to the FBI affidavit, Cole lives in a single-family home with his mother and other relatives in Woodbridge, approximately 30 miles from Washington. He works in the office of a bail bondsman in northern Virginia.

Prince William County Public Schools confirmed to multiple outlets that Cole graduated from Hylton High School in 2013. USA Today reported he does not have a criminal history but has received several traffic violations in the years since the pipe bombs were placed. The Associated Press reported he was not registered to vote.

Neighbors described Cole as reclusive. Several told CNN they frequently spotted him taking long walks through the subdivision with his pet Chihuahua, often wearing headphones.

"Nothing ever happens here," one neighbor told NBC News. "It's like Sleepytown."

First court appearance

Cole appeared before Magistrate Judge Moxila Upadhyaya on Friday afternoon for his initial court appearance. He was wearing a tan jumpsuit and glasses as the judge read him his rights.

Six members of Cole's family attended the hearing and were visibly emotional. After the proceeding concluded, they called out to him.

"We love you Brian," they said. "We're here for you baby."

The judge set a detention hearing for December 15, at which prosecutors will seek to have Cole held pending trial.

Years of investigation

The arrest ends one of the FBI's longest-running unsolved cases. Over nearly five years, investigators reviewed approximately 39,000 video files, conducted more than 1,000 interviews and received over 600 tips. The reward for information leading to an arrest was increased from $50,000 to $100,000, and eventually to $500,000.

Agents pursued multiple investigative avenues, including subpoenaing credit card data from retailers to identify people who purchased battery components believed to be used in the devices. They also obtained Nike sales data after determining the suspect wore Nike Air Max Speed Turf sneakers, but those leads did not produce a breakthrough.

FBI Director Kash Patel said investigators brought in a new team of experts this year to re-examine the evidence.

"We brought in a team of experts who were the best at what they do in their specific fields to reevaluate that evidence, to dive back in, and to not come back with a 'no' for an answer until they had found the suspect," Patel said.

FBI Deputy Director Dan Bongino said the arrest sends a message.

"You're not going to walk into our capital city, put down two explosive devices and walk off in the sunset," Bongino said. "Not going to happen — we were going to track this person to the end of the Earth."

Bondi criticized the pace of the investigation under the previous administration.

"This cold case languished for four years," she said.

Greg Rosen, who led the now-defunct Capitol Siege Section of the U.S. Attorney's Office for the District of Columbia, offered a different view.

"This is a testament to the incredible work of career FBI agents and prosecutors who have been working this case for years," Rosen told NBC News. "While we don't yet know all the facts, the American people should be proud of their work."