US first lady Michelle Obama hugs students at Martin Luther King middle school, an all-girls school in Dakar, Senegal June 27 2013. US President Barack Obama and his wife Michelle are visiting Senegal until June 28 before travelling to South Africa and Tanzania.[Photo/Agencies]

US President Barack Obama and first lady Michelle Obama are pictured at the 'door of no return' as he visits the Maison Des Ecslaves, the gathering point where African slaves were shipped west until the mid-19th century, at Goree Island near Dakar, Senegal, June 27, 2013. [Photo/Agencies]

Senegalese women watch as US President Barack Obama's motorcade drives past on his way to meet with Senegal's President Macky Sall at the Presidential Palace in Dakar, June 27, 2013. [Photo/Agencies]

Members of Senegal's government wait to greet US President Barack Obama and first lady Michelle Obama in Dakar June 26, 2013. The first family arrived in Senegal on Wednesday, the first of three countries on their week-long trip. [Photo/Agencies]