The public prosecutor in Egypt has frozen the assets of 14 senior Islamists as part of an investigation into the incitement of violence.
The BBC reports that Muslim Brotherhood head Mohammed Badie and his deputy Khairat al-Shater are among them.
Mr Badie and other Brotherhood figures are already the subject of arrest warrants, while the ousted President Mohammed Morsi remains in custody.
The decision by Egypt's public prosecutor Hisham Barakat to freeze the assets of senior Islamists comes amid an ongoing investigation into deadly clashes that have happened since President Morsi was ousted.
Dozens of people have died during major demonstrations by pro and anti-Morsi protesters in the past two weeks.
According state TV, the leader of the Brotherhood's Freedom and Justice Party Mohammed Saad al-Katani has also been affected by the asset freeze, along with senior figures in rival Islamist groups.
Meanwhile, Egypt's new interim prime minister Hazem al-Beblawi has begun appointing people to senior cabinet posts.
Mr Morsi's supporters, many of them members of the Muslim Brotherhood, have been staging a mass sit-in Cairo since their man was removed from power on 3 July.
They are demanding his reinstatement as president and say the military's removal of him amounted to a coup.
However the army says it intervened to remove Mr Morsi in response to protests by millions of Egyptians who accused him of becoming increasingly authoritarian and failing to tackle economic difficulties.