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– A well-known public relations consultant in San Francisco is now the target of a nationwide manhunt after police found explosives in his apartment. The agency says Ryan Kelly Chamberlain II, 42, should be considered armed and dangerous and may be in possession of more explosives, USA Today reports. He was last seen south of San Francisco yesterday, driving a white 2008 Nissan Altima with California or Texas license plates, reports NBC. Police, hazmat teams, and federal agents spent 14 hours searching Chamberlain's residence yesterday and witnesses say some devices were exploded at the scene. Chamberlain was well-known in the city's political circles and worked on many campaigns, focusing on social media, the San Francisco Chronicle finds. "I'm worried about the guy," the founder of Barbary Coast Consulting says. "I'm hoping this ends without anybody getting hurt. I'm flabbergasted that this seems to be taking place." A former colleague says Chamberlain "got weird" after losing his job at a sports marketing company last fall. "There was a lot of strange behavior since November," he says. "He stopped answering his phone. I think he became an extreme introvert."

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A self-described political junkie with an extensive background in Bay Area public relations is the subject of a nationwide manhunt after FBI agents said they found explosives in his San Francisco apartment. 
  
 Ryan Kelly Chamberlain II, 42, is considered armed and dangerous, said FBI spokesman Peter Lee. More than two dozen federal agents, hazardous material crew members, police and firefighters raided his residence Saturday at 1831 Polk Street. 
  
 Lee provided few details about the investigation during the agency's first press conference on the probe Sunday, but said Chamberlain is probably driving a white Nissan Altima with either California or Texas license plates 7FQY085 and BX9M042 respectively. 
  
 The agency said Chamberlain is wanted for allegedly possessing explosives in his home. Lee said agents believe Chamberlain was acting alone. Authorities declined to describe the type of explosives found at the apartment. Nor did they state why the suspect may have amassed the material, saying the investigation is still ongoing. 
  
 No biological threats 
  
 Contrary to some media reports, authorities said, they did not find any ricin or other chemical or biological threats in the residence. But, Lee said, "He did possess explosives at his residence." 
  
 Photos released by the FBI match pictures of Chamberlain that accompany his online profiles. He is 6-foot-3 and weighs 225 pounds with brown hair and blue eyes. He was last seen wearing a hooded sweatshirt and blue jeans, Lee said. Authorities said anyone who encounters him should call 911 rather than approach him. 
  
 Chamberlain is a familiar face in San Francisco's political circles who has worked on many campaigns, focusing on social media, said Alex Clemens, founder of San Francisco's Barbary Coast Consulting. 
  
 "It's a small pond, and people in the industry tend to know each other," he said. 
  
 In October 2009, Clemens contracted with Chamberlain to work on a campaign. 
  
 "I'm worried about the guy. I'm hoping this ends without anybody getting hurt. I'm flabbergasted that this seems to be taking place," he said. 
  
 Known in political circles 
  
 Mark Mosher, creative director of San Francisco consulting firm BMWL, said Chamberlain was hired by almost every local political consulting firm at one point or another. As recently as Friday, he was chiming in on Mosher's Facebook feed about gun control and mental health. 
  
 "When I heard one of my business partners text me about this (manhunt), I thought he was joking," Mosher said. 
  
 Jessica Schlenoff, a high school tutor who works from home and lives in an adjacent apartment complex, was watching as agents wearing gas masks and protective jumpsuits swept through the building Saturday. 
  
 She has known Chamberlain for more than a decade and was shocked to learn his apartment was the one raided. 
  
 "It's so surprising. No one can believe it," she said. 
  
 Chamberlain, a Bay Area native, attended the University of Iowa before embarking on a career as a music journalist in Des Moines, according to his online resume. He later moved to San Francisco, and at age 30, made a bid for a spot on the Republican Party County Central Committee in San Francisco, an organization that governs the local party and doles out critical endorsements. 
  
 During the 2012 NFL season, Chamberlain was an independent contractor for The Chronicle and tweeted and posted links to Facebook to boost coverage for the San Francisco 49ers Insider iPad app. 
  
 Most recently, he worked in public relations for several Bay Area tech, apparel and marketing companies. 
  
 'Got weird' after job loss 
  
 In November, he was let go from Project Sport, a San Francisco sports marketing company where he worked with professional athletes. 
  
 Randy Bramblett, 32, a professional cyclist and personal trainer in San Francisco, knew Chamberlain through Project Sport and would often get beers with him and others from the company after events. 
  
 Bramblett said that Chamberlain was "emotionally charged" and that when he lost his job he "got weird." 
  
 "The thing is, there was a lot of strange behavior since November," Bramblett said. "He stopped answering his phone. I think he became an extreme introvert." 
  
 While former co-workers may have lost touch with Chamberlain, he continued to post to social media using the Twitter handle@poliholic where he tweeted about sports, news and music. He made light of a recent viral Bay Area story where a mysterious man was hiding cash around San Francisco. 
  
 "Deft move@Hidden Cash, leaving $ in the pocket of that suit coat I rarely wear. I found it without a clue! But how'd you get into my apt?" Chamberlain tweeted Friday. 
  
 Chamberlain is listed as a lecturer at the University of San Francisco on the university's website. His profile touts his experience in journalism, public relations and marketing. Chamberlain taught one course for one semester as an adjunct professor in 2011, said Anne-Marie Devine, a spokeswoman for the university. 
  
 Chronicle staff writer Benny Evangelista contributed to this report. ||||| From NBC Bay Area 
  
 The FBI has launched a nationwide manhunt for a man named Ryan Kelly Chamberlain II in connection with Sunday's investigation at an apartment building in San Francisco's Russian Hill neighborhood. 
  
 FBI agents, San Francisco police and fire crews, and a hazardous materials team swarmed the building between Jackson and Polk streets early Saturday morning in a search that continued into the early hours of Sunday. 
  
 FBI spokesperson Peter Lee said at a press conference Sunday that the FBI is looking for Chamberlain, 42, a San Francisco resident, for possession of explosive material at his residence. 
  
 Chamberlain is 6' 3" tall, weighs 225 lbs and has blue eyes and brown hair, according to Lee. He was last seen south of San Francisco Sunday, driving a white 2008 Nissan Altima with a California or Texas license plates of either 7FQY085 or BX9M042. He is believed to be wearing a dark blue hooded sweatshirt and blue jeans and is considered armed and dangerous, Lee said. 
  
 The FBI is encouraging anyone with any information on Chamberlain to notify the agency at 415-553-7400 or call 911. 
  
 The San Francisco FBI office told NBC Bay Area Sunday that the agency was executing a search warrant at Chamberlain's apartment as part of a criminal investigation. 
  
 the FBI said the investigation poses "no threat to public safety," and that protective equipment had been used Sunday in the interest of agent safety. Lee said that contrary to what was reported by some news sources, there was no conclusive evidence of the deadly poison ricin at Chamberlain's apartment. 
  
 An FBI spokesperson said that a bomb squad had shown up at the scene of the investigation, but that it turned out to be a false radiation alarm. 
  
 An FBI source told NBC Bay Area that crews found a chemical in the apartment that, if not handled correctly, can kill. The person may have bought the chemical -- which is often used in assisted suicide situations -- on the internet, according to the source. 
  
 The FBI declined further comment on the intent or motive behind the explosive material in light of the ongoing investigation. 
  
 "Actually, as I was walking down here, I thought it was a film set," onlooker Faisal Choudry said. "And somebody said the FBI is here investigating, and they’ve been here since the morning." 
  
 Police blocked off a section of Jackson Street between Polk Street and Van Ness Avenue Saturday. Jackson street was reopened around 12:30 a.m. and fire and hazmat crews left the scene Sunday morning. 
  
 Those who live in the area said it had been an interesting afternoon. 
  
 "There are a lot of police, a lot of fire, and there was a bomb squad here earlier," neighbor Dianne Dubois said. "That's very scary for those of us who live here, but it seems like everything is going OK. But it's hard to know. We don't know anything about what's going on, so we have no information at all." 
  
 Neighbors said that the FBI had not told them anything about the investigation. 
  
 "It seems a bit more chaotic down here than it was inside," neighbor Tiffany Fechtar said. "The person’s door is open. There’s stuff outside. They’ve got the hazmat suits on, and I don’t know. what’s going on." 
  
 Those who live inside the building told NBC Bay Area the FBI has taken at least two computers from the apartment. 
  
 FBI via AP This undated image provided by the FBI shows Ryan Kelly Chamberlain, II, who is being sought by the FBI, who has issued a nationwide alert to law enforcement agencies about this man they consider armed and dangerous who is wanted for investigation of possessing explosives. 
  
 Neighbors said they do not know much about the man who lives in the unit except he is in his 40s and works in marketing. They described him as quiet and polite. 
  
 "I know this person who lives in this apartment," Fechtar said. "It’s just kind of weird. He seems like a nice guy, and he probably is." 
  
 When reporters asked Lee whether the FBI is using Chamberlain's apparent social media presence to help with the investigation, Lee declined comment or confirmation that the online accounts belonged to Chamberlain. 
  
 Chamberlain's warrant and affidavit are currently sealed, Lee said. His apartment is being treated as an active crime scene and currently remains sealed, he said. 
  
 Crews wearing hazmat suits were seen going in and out of the building and people gathered on the roof of the building, according to a witness. More than a dozen bags of evidence were collected Saturday. 
  
 First published June 1 2014, 8:04 PM ||||| Political and media consultant at center of explosives manhunt is in custody. 
  
 This undated image provided by the FBI shows Ryan Kelly Chamberlain, II, who is suspected of possessing explosives. (Photo: AP/FBI) 
  
 SAN FRANCISCO – The FBI reports a man who was the subject of a manhunt after suspicions that he had explosives was in custody Monday night. 
  
 The arrest of Ryan Kelly Chamberlain II, 42, of San Francisco came after reports from the FBI that he was no longer an immediate threat and that the agency had received word of a credible sighting at a bar. 
  
 Earlier Monday, reports surfaced that the political and media consultant sent out a timed suicide note via social media Monday morning. 
  
 FBI spokesman Peter Lee said Chamberlain was last seen Sunday. 
  
 In a three-page letter titled "Goodbye" timed to go out to his Facebook connections Monday morning, Chamberlain wrote that he has dealt with depression "for as long as I can recall" and that he was saying farewell to family and friends, the San Francisco Chronicle reports. 
  
 Chamberlain discussed issues in the note involving a romantic heartbreak, lost of a job and his mother, who he described as a "religious addict certain that the Rapture is coming any day now." 
  
 The FBI said Chamberlain was considered armed and dangerous. He was believed to be traveling in a white 2008 Nissan Altima with Texas license plates. 
  
 Police and federal agents spent 14 hours searching Chamberlain's apartment in San Francisco's Russian Hill neighborhood Saturday. 
  
 "There were people all over the building in hazmat suits," said Jessica Schlenoff, who lives across the street from Chamberlain's building. 
  
 Agents in hazardous material suits are seen as the FBI searches a building in San Francisco. (Photo: AP/Michael Short, San Francisco Chronicle) 
  
 She said police on the scene told her they exploded some devices. 
  
 Chamberlain graduated from Iowa State University in 1993 with majors in journalism and political science. He wrote music reviews for The Des Moines Register in 1995 and 1996. Some of his work included concert reviews of Van Halen, Hootie & the Blowfish and Brooks & Dunn. 
  
 A Des Moines Register article from 1994 said Chamberlain previously worked as promotional director at Hooter's of Des Moines, and in Sen. Chuck Grassley's Washington, D.C., office. Grassley's office could not confirm Sunday whether Chamberlain worked there. 
  
 Schlenoff said she had known Chamberlain slightly for several years, seeing him on the street and on social occasions. 
  
 "He was a pretty normal guy," she said. "I would never ever have thought that this was a dangerous person at all." 
  
 Contributing: Melanie Eversley in New York, Sharyn Jackson, The Des Moines Register; The Associated Press 
  
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