CAIRO (Reuters) - Egypt's Muslim Brotherhood said its leaders had not been detained by midday on Wednesday after prosecutors ordered them arrested on charges of inciting violence.

Spokesman Gehad El-Haddad said the announcement of charges against Mohamed Badie and several other Brotherhood leaders was an attempt by the authorities to break up a vigil by thousands of Brotherhood supporters demanding the reinstatement of Mohamed Mursi, ousted as president by the army last week.

The charges were "nothing more than an attempt by the police state to dismantle the Rabaa protest", he said by telephone from the vigil at Rabaa Adaweya mosque in northeast Cairo. He said some of the leaders whose arrest was being sought were now at the site of the protest.

(Reporting by Maggie Fick; Writing by Peter Graff; Editing by Alison Williams)