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Brad Smith, a student at San Diego State University and a tenant of Boulevard 63 Apartments, said apartment complex managers told him to remove the American flag he was displaying on his apartment's balcony because it "could offend foreign people."

Smith said that when he asked management about the notice he received ordering him to remove the flag, they reportedly told him "it was for political reasons and that the flag could offend foreign people that live here, foreign exchange students."

ABC News' investigation revealed that the rules of Smith's lease prohibit signs or other personal property from being kept outside the premises, and that management determines what is "permissible and acceptable."

But Smith asserts this is not the explanation he was given.

"This was never brought to my attention," Smith said. "I've had friends and family fight to defend that flag."

The apartment complex called the incident a "misunderstanding," and has since amended its rules to permit the display of state and country flags.