CAIRO — Remnants of Egypt’s old government reasserted themselves on Thursday within hours of the military ouster of the country’s first freely elected president, in a crackdown that left scores of his Muslim Brotherhood backers under arrest, their television stations closed and former officials restored to powerful posts.

The actions provided the first indications of what Egypt’s new political order could look like after Mohamed Morsi, the Islamist president in power for only a year, was deposed by Egypt’s military commanders on Wednesday evening.

The commanders, who installed an interim civilian leader, said they had acted to bring the country back together after millions of Egyptians demonstrated against Mr. Morsi, claiming he had arrogated power, neglected the economy and worsened divisions in society.

But Mr. Morsi’s downfall and the swift effort that followed to repress the Muslim Brotherhood enraged its constituents. They called for demonstrations nationwide on Friday, which could provide a telling test of the interim government’s claims of inclusiveness toward all segments of Egypt’s population.