Magdy Hussein, a leader of the Anti-Coup Alliance that has spearheaded protests demanding Morsi's reinstatement, was arrested at dawn at his house, the security officials said.
He faces charges of inciting violence and threatening national security and stability.
Also detained was Nasr Abdel Salam, head of the Building and Development party, the political arm of Gamaa Islamiya, a former militant group that has since renounced violence.
Two other leaders of the party, which is part of the Anti-Coup Alliance, were also arrested.
Police also arrested Hossam Khalaf, a leader of the moderate Islamist party Wassat, security officials said. Khalaf, whose party is also part of the pro-Morsi alliance, was accused of inciting violence.
The Anti-Coup Alliance condemned the arrests as "kidnappings" and renewed its call for pro-Morsi protests during a "day of rage" on Thursday, the anniversary of his removal from office.
Then army chief Abdel Fattah al-Sisi led the ouster of Morsi after millions rallied against the Islamist's divisive one-year rule. Sisi was elected to replace Morsi in a May landslide.
Since Morsi's ouster, the alliance has led regular protests against the new authorities, but its rallies have shrunk amid the brutal crackdown.
Hundreds of Morsi supporters have already been sentenced to death after speedy trials.
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He faces charges of inciting violence and threatening national security and stability.
Also detained was Nasr Abdel Salam, head of the Building and Development party, the political arm of Gamaa Islamiya, a former militant group that has since renounced violence.
Two other leaders of the party, which is part of the Anti-Coup Alliance, were also arrested.
Police also arrested Hossam Khalaf, a leader of the moderate Islamist party Wassat, security officials said. Khalaf, whose party is also part of the pro-Morsi alliance, was accused of inciting violence.
The Anti-Coup Alliance condemned the arrests as "kidnappings" and renewed its call for pro-Morsi protests during a "day of rage" on Thursday, the anniversary of his removal from office.
Then army chief Abdel Fattah al-Sisi led the ouster of Morsi after millions rallied against the Islamist's divisive one-year rule. Sisi was elected to replace Morsi in a May landslide.
Since Morsi's ouster, the alliance has led regular protests against the new authorities, but its rallies have shrunk amid the brutal crackdown.
Hundreds of Morsi supporters have already been sentenced to death after speedy trials.
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