OAKLAND, Calif. -- A Southern California man was arrested at Oakland International Airport after security officers found him wearing an unusual watch they said could be used to make a timing device for a bomb, authorities said Friday.

Geoffrey McGann, 49, of Rancho Palos Verdes was taken into custody Thursday night after he tried to pass through airport security with an ornate watch that had switches, wires and fuses, according to Sgt. J.D. Nelson, a spokesman for the Alameda County Sheriff's Department.

A bomb squad arrived within five minutes and determined there were no explosive materials in the watch, Nelson said. The checkpoint was closed while officers secured the area.

McGann was taken to Santa Rita Jail in Dublin where he was charged with possessing materials to make an explosive device, sheriff's officials said. He was still in custody Friday night and could not be reached for comment.

McGann told Transportation Security Administration officers that he's an artist and the watch is art, Nelson said.

While no actual explosives were found, McGann was carrying potentially dangerous materials and appeared to have made alterations to his boots, which were unusually large and stuffed with layers of insoles, Nelson said.

A profile for a person named Geoffrey McGann on the website LinkedIn.com lists him as the owner and creative director of a media production company called Generator Content. He attended the Art College Center of Design in Pasadena from 1984 to 1987, according to the website.