Yemen's Nobel Peace Prize Tawakul Karman has been denied entry into Egypt after she landed at Cairo airport "for security reasons", officials say. Ms Karman, the first Arab woman to win the prestigious prize, was held on arrival and ordered to fly on the same plane back to the Gulf.
She has voiced support to Muslim Brotherhood followers, calling Mohammed Morsi's ousting "undemocratic".
Separately, US diplomat William Burns continued mediation talks in Cairo.
The deputy secretary of state extended his visit to meet Egyptian army chief Gen Abdul Fattah al-Sisi and a pro-Morsi delegation on Sunday.
He earlier met members of Mr Morsi's Muslim Brotherhood and its political party, as well Foreign Minister Nabil Fahmy. Mr Burn's visit is the latest in a flurry of US and EU diplomatic activity to mediate a peaceful resolution to the crisis, which, since 3 July, has led to the deaths of more than 100 Morsi supporters.
