The family of one of Egypt's most prominent pro-democracy activists, Alaa Abdel-Fattah, says security forces have re-arrested him while he was under probation.
His mother, Laila Soueif, tells The Associated Press that Abdel-Fattah was arrested on Sunday from Dokki police station in Cairo, where authorities have required him to spend the night since his release in March after serving a five-year sentence for taking part in protests in 2013.
A security official says Abdel-Fattah was taken to prosecutors for an investigation into claims he has called for protests.
The official spoke on condition of anonymity because they were not authorised to brief media.
His arrest comes amid a wider crackdown on dissent since rare anti-government protests last week. Over 2,000 people were arrested, according to lawyers.