NEW : Ryan Kelly Chamberlain II was arrested in Crissy Field , a law enforcement official says . Ryan Kelly Chamberlain II , Saturday , is accused of having explosive materials at his home . He was last seen 42 south of Crissy Field , according to the KTVU .
NEW : Chamberlain was arrested in Crissy Field , a law enforcement official says . Ryan Kelly Chamberlain II , 42 , is accused of having explosive materials at his home . He was last seen Saturday south of San Francisco , according to the FBI .