GENEVA, July 5 (Reuters) - U.N. human rights chief Navi Pillay said on Friday she was concerned by reports of the detention of leading members of Egypt's Muslim Brotherhood, but stopped short of saying whether their overthrow this week constituted a coup d'etat.

Her spokesman Rupert Colville told a regular U.N. briefing that specific crimes would need to have been committed to justify the detentions, and said Egypt's new rulers should make clear why the figures were being detained or release them. (Reporting by Tom Miles; Editing by Kevin Liffey)