CNN Beijing correspondent Emily Chang was detained for two hours today by authorities in Shanghai for holding up a t-shirt that depicts Pres. Obama wearing a Red Army uniform.

Chang bought the t-shirt at a basement souvenir shop in Beijing and brought it with her to Shanghai as she covers Pres. Obama's visit to the city.

When Chang held up the shirt up for a live shot outside a Shanghai metro stop, she was approached by two security guards. "They scrambled towards us and tried to pry the shirt out of my cold, dead hands," Chang writes on the In the Field blog. "I didn't give in." Despite "a bit of yelling and quite a scuffle," the crew kept the shirt.

The front of the t-shirt says "Serve the People" in Chinese. On the back, it reads "Oba Mao" in English. The shirts have been seen in Chinese shops for months, but were "banned" ahead of Obama's trip.

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