Los Angeles, Oct. 5 -- The Federal Bureau of Investigation arrested a California real estate agent at Los Angeles International Airport on Sunday following disclosures to CBS News from law enforcement sources that she had allegedly surveilled the US-based son of Taiwan's president.

Wanying "Heather" Zhang, 34, was taken into custody by federal law enforcement officials at LAX prior to boarding a scheduled flight destined for Shanghai, China, facing formal charges of acting as an unregistered agent of a foreign government.

Edric Ding, Zhang's husband and a fellow realtor at the same firm, told CBS News during a telephone interview on Sunday that "I don't know anything yet", while declining to offer further remarks.

It remained undetermi...