Arlington County police have confirmed that James Yoo was the man at the center of the standoff at the Virginia home that exploded Monday night.
Police Chief Andy Penn said the 56-year-old owned the two-story duplex and was the only person in the building at the time. Yoo is presumed dead.
"Human remains have been located at the scene, and the office of the chief medical examiner will work to positively identify the individual and determine the cause and manner of death," Penn told reporters during an afternoon news conference on Tuesday.
Three officers reported minor injuries, but none was transported to the hospital. No other injuries were reported. Police evacuated surrounding neighbors well before the explosion.
Officials said they are still investigating the cause of the massive explosion that leveled the home and rocked Arlington's Bluemont neighborhood.
Assistant Fire Chief Jason Jenkins noted that the fire department turned off the gas line to the house before the explosion occurred. Bomb-sniffing dogs are on the scene, he said.
Video posted to social media showed the house disappearing under a ball of fire, lobbing debris into the night air and sending wreckage raining down onto the suburb of Washington, D.C. Neighbors said the blast could be heard and felt for miles.
Video of the explosion. Hope everyone was out of the house#Arlington #ballston @ARLnowDOTcom @RealTimeNews10 pic.twitter.com/JSZE7LkoTD
— c “” maj (@connormaj) December 5, 2023
What happened in the moments leading up to the explosion?
Arlington County police had initially been called to the brick duplex around 4:45 p.m. ET after reports of a shots-fired incident. Upon arriving, they discovered Yoo had shot more than 30 rounds of a flare gun into the surrounding neighborhood.
Penn said officers attempted to engage with Yoo to no avail, so they obtained a search warrant. When they breached the front door, the emergency response team was met with "multiple gunshots from a firearm coming from within the dwelling," Penn said.
In an effort to compel Yoo to surrender, Penn said the officers deployed "nonflammable, less-lethal chemical munitions" where Yoo was believed to be hiding. But those measures also failed to draw him out.
Then at around 8:25 p.m. came the flaming eruption.
The exact circumstances of the explosion are still under investigation. The Bureau of Alcohol, Tobacco, Firearms and Explosives said federal fire agents are assisting the investigation.
What we know about James Yoo
Penn said Yoo did not have any previous interactions with officers at the address of the now-obliterated home. The only documented incidents between Yoo and law enforcement, he said, are two calls for service for loud noise over the past couple of years.
Penn noted that officials are aware of "concerning" social media posts allegedly made by Yoo, adding that they will be reviewed as part of the investigation.
The police chief stressed that the events are an isolated incident and said there is no ongoing threat to the community.
David Sundberg, assistant director in charge of the FBI's Washington Field Office, told reporters that Yoo had communicated with the FBI via phone calls, online tips and letters over a number of years.
"I would characterize these communications as primarily complaints about alleged frauds he believed were perpetrated against him," Sundberg told reporters. "The information contained therein and the nature of those communications did not lead to opening any FBI investigations."
A public records search shows the house had been owned by Yoo since 1992.
Chris White, a tech executive living in California, told NPR that he rented the house that exploded from Yoo and his wife from 2015 to 2016.
"They were incredibly normal and, in fact, some of the best landlords that I've had," White told NPR on Tuesday.
He added that Yoo, then based in Rochester, N.Y., would give notice ahead of maintenance work, was generous in handling tenant requests and responded "totally reasonably" when White decided to break his lease early.
White said he believed Yoo owned other rental properties. Yoo signaled his intention to sell the Arlington address when White ended his lease in 2016 in a written notice of sale.
What did neighbors see and hear?
Residents could hear and feel the explosion for miles around Arlington County, where the average population is over 9,000 people per square mile.
Kathleen Boyce, who lives just around the block, said she was watching the house through a gap in her neighbor's yard after hearing sirens all night.
"I heard this pounding, and I thought maybe it was the police in the street," she recalled on Tuesday. "Then there was an explosion, and I could see it went up 30 or 40 feet in the air."
"I've lived here more than 20 years," she said, adding that the explosion knocked down some of her wall hangings. "I walk past there all the time. It's a little frightening to think what's going on in these houses."
Alex Wilson, who lives across the street from the house, told NPR that the man who lived there appeared to be a bit of a recluse: He lived alone, seldom left the property and covered the windows in foil so no one could peer inside.
With his cellphone's camera, Wilson captured video of the inferno, which has been replayed countless times on local news stations. He said he heard police announce they were going to try to ram the front door, so he went on his roof to start recording.
"That's when the whole thing went up in hella fashion," he said. "I've never seen an explosion like that. My buddy who served in Afghanistan never saw an explosion like that."
Allison Van Lare said she felt the explosion nearly 3 miles away in her neighborhood of Shirlington.
"I heard something like air popping, and then the fence started rattling intensely, almost like a sonic boom," she said.
The explosion also attracted the attention of top officials.
U.S. Rep. Don Beyer, who represents the area, thanked first responders and said he was monitoring the "very, very scary" circumstances.
Monitoring the emergency response to a major explosion in the Bluemont neighborhood of Arlington tonight. This is very, very scary, and my profound thanks go out to first responders working to secure the area and keep everyone safe.
— Rep. Don Beyer (@RepDonBeyer) December 5, 2023
A fire that raged in the explosion's aftermath was deemed under control as of 10:30 p.m., but crews continued to extinguish smaller spot fires throughout the evening, according to the Arlington County Fire Department.
More than 160 power outages were initially reported in the area, but that number had decreased to 19 as of Tuesday morning.
