A search of social media expert Ryan Chamberlain's San Francisco apartment turned up ball bearings, screws and the components needed to make a bomb that federal agents think was intended to kill, the FBI said in an affidavit unsealed Tuesday.
The discovery was disclosed as Chamberlain was charged in federal court, after his Monday night arrest capped a nationwide manhunt that began when authorities say they found explosive materials in his home.
Until Tuesday, it had been unclear what investigators had found over the weekend that prompted that manhunt.
"FBI bomb technicians believe that the device was designed to maim or kill a human being or human beings,'' FBI Special Agent Michael Eldridge said in the affadavit.
A circuit board described in the document was designed to serve as a remote control, allowing detonation of the device from afar, Eldridge said.
Investigators said they found the materials inside a bag at Chamberlain's apartment during a search over the weekend. The discovery prompted the nationwide manhunt for the 42-year-old.
The FBI has not said what, if any, specific plans Chamberlain might have had for the device, or how they were alerted to the material.
Chamberlain appeared in federal court after being charged with one count of possession of an illegal destructive device. He was accompanied by a public defender but did not enter a plea. He wore the same shorts and shirt that he had on when he was arrested Monday near the Golden Gate Bridge.
Though Chamberlain was considered armed and dangerous, FBI spokesman Peter Lee said Monday during the manhunt that he did not seem to pose an immediate threat to public safety.
"Anyone who has the means, methods and access to make a bomb should be considered armed and dangerous,'' Lee said before the arrest.
FBI Special Agent in Charge David Johnson said authorities had served a search warrant at Chamberlain's home near Polk and Jackson streets in the city's Nob Hill neighborhood on Saturday and found explosive materials there.
A nationwide manhunt ensued for Chamberlain, who on Monday posted what appeared to be a suicide note on social media detailing his struggles with depression and trouble with family and work.
Chamberlain was arrested Monday night near Crissy Field in San Francisco at about 6:30 p.m. after a tip from a member of the public and an electronic record of an ATM withdrawal from a San Francisco bar led police to the suspect in his car, FBI officials said.
Tuesday morning, Chamberlain was brought before a federal magistrate in San Francisco and was charged with one count of illegal possession of a destructive device.
The FBI says the materials discovered at the home could have caused great harm to the public.
According to the criminal complaint, bomb technicians searched a messenger bag in Chamberlain’s apartment and found:
- “A screw top glass jar containing batteries and a powdery, green substance”
- “A model rocket motor lodged within the green powdery substance”
- “An ‘electric match,’ a common igniter for improvised explosive devices (‘IEDs’)”
- “An assortment of ball bearings and screws believed to be intended projectiles”
- “A wire extending from the glass jar attached to the metal lid of the jar”
- “A circuit board, configured as a remote-controlled receiver”
In court Tuesday morning, Chamberlain was told of the federal charge at his initial appearance before U.S. Magistrate Nathaniel Cousins, who scheduled a detention hearing at 9:30 a.m. Thursday and ordered Chamberlain held in custody until then.
The magistrate also scheduled a status conference in the case for 11 a.m. Wednesday.
San Francisco Police Chief Greg Suhr praised the public for their help in locating Chamberlain.
"The system worked in this case, and we got someone off the street before he hurt himself or someone else," Suhr said.
"Unbelievable police work, unbelievable collaboration with our federal partners to get somebody who was absolutely growing more desperate by the moment, in crisis," he said.
FBI officials said that the bomb-making materials allegedly found in Chamberlain's apartment Saturday have been sent to the agency's headquarters in Washington, D.C., for further examination.
They confirmed that, if put together, the materials had the potential to be an improvised explosive device, or IED.
Johnson said the device would have caused significant damage had the parts been put together.
Authorities admitted that they were surprised that Chamberlain remained in San Francisco, given that he was the subject of a nationwide manhunt.
FBI officials confirmed that a man fitting Chamberlain's description was seen using an ATM at the bar Mad Dog in the Fog, located at 530 Haight St., between 2 and 3 p.m. Monday and then stayed at the bar for a while before heading to Crissy Field, where he was eventually captured by police.
Chamberlain will remain in custody until then, and he faces up to 10 years in prison if convicted of the charge.
FBI agents and San Francisco police spent part of the day Tuesday searching a second flat Chamberlain rented on Vallejo Street, a few miles away from his Polk Street apartment.
Landlord Douglas Kwan said he is concerned.
“My fear is the worst-case scenario where somebody has explosives in their other apartment,” Kwan said. “I assume there could be explosives here and that's my biggest fear.”
Kwan said he suspected Chamberlain had been illegally subletting the Vallejo flat, so he hired a private investigator to follow Chamberlain. When confronted, Chamberlain claimed he was renting the Polk Street place for his girlfriend to protect her from a stalker.
Kwan said fears he may have been Chamberlain's target.
“Given the fact we're trying to evict him for illegal fraud, I feel he may have wanted to get me,” Kwan said.
Over the past 15 years, Chamberlain has worked in public relations and on many local political campaigns, including Lt. Gov. Gavin Newsom’s when he ran for mayor in San Francisco.
Chamberlain also worked as an independent contractor for the San Francisco Chronicle during the 2012 NFL season, doing social media to boost coverage for the San Francisco 49ers Insider iPad app, the newspaper said.
Suhr at Tuesday morning's news conference made a plea to the public to alert authorities if they suspect someone is in crisis.
"If anyone knows anybody who is in crisis or is in a dark place, please report that to us, we have more resources in San Francisco than maybe anywhere else to help somebody in crisis before they harm themselves or others. If you think it's coming, please tell us now," Suhr said.
NBC Bay Area's Jodi Hernandez, Bay City News and the Associated Press contributed to this report.