Seventeen members of the outlawed Muslim Brotherhood were detained on Wednesday on suspicion of engaging in banned political activity, an Egyptian security official said.
The Brotherhood is Egypt's largest opposition group. Though officially banned, members have run for political office as independents, and they hold about a fifth of the seats in Egypt's parliament.
The security official said that Egypt's prosecutor issued 15-day detention orders for those who were arrested Sunday while holding a meeting in the Nile Delta region.
The official spoke on condition of anonymity because he wasn't authorized to speak to the press.