Visiting US first lady Michelle Obama toured China's Great Wall on Sunday, after her arrival at the US embassy in Beijing earlier in the day sparked a minor security alert. Vendors at the tourist site northeast of the capital appeared to have removed T-shirts which are normally on sale showing President Obama in a Mao hat, with one merchant revealing a boxful of the souvenirs stored in the back of her tent. Earlier in the day, as Obama's motorcade arrived at the US embassy for a roundtable with educators, parents and students, two people just outside the premises began shouting. Since arriving in the capital on Thursday night, Obama -- whose mother is also accompanying her -- has also played table tennis with students and toured the Forbidden City with her counterpart Peng Liyuan.
