FBI Launches Manhunt for Explosives Suspect

June 1, 2014— -- The FBI today asked for the public's help in the search for a San Francisco man, after investigators searching his apartment allegedly found explosive materials.

According to the FBI, Ryan Kelly Chamberlain II, 42, is wanted for allegedly possessing explosive materials, and should be considered armed and dangerous.

"Anyone who possesses explosives should be considered armed and dangerous," FBI spokesman Peter Lee said.

But Lee said that Chamberlain "has not made any threats that I know of."

"There is no threat to public safety at this time that we know of," he said.

Chamberlain was last seen Saturday, south of San Francisco, Lee said.

Chamberlain is described as a white male, 6'3" and 225 pounds with brown hair and blue eyes.

He was last seen wearing a dark blue sweatshirt and blue jeans driving a white 2008 Nissan Altima with either California plate 7FQY085 or Texas plate BX9M042.

The announcement today comes after FBI agents, San Francisco police and fire crews, and a hazardous materials team swarmed Chamberlain's apartment in the Russian Hill neighborhood Saturday morning.

There were initial reports that law enforcement sources told reporters a large amount of ricin was found, but Lee said today those reports were false.

Anyone with information regarding the whereabouts of the suspect is urged to contact their nearest FBI office or dial 911. The FBI can be reached 24 hours a day at 415-553-7400 in the San Francisco area. All calls are confidential. Tips can also be submitted at: tips.fbi.gov.