Egyptian blogger and activist Ahmed Doma announced on Tuesday that he had been arrested by the police while he was at his home in Cairo.
"I am now in the Al-Pasateen police station," Doma wrote on his Facebook page. "I do not know why I have been arrested or what the charges against me are."
Doma was an active critic of the ousted Egyptian President Hosni Mubarak, and then of the Military Council that ran the country after the 25 January Revolution.
Recently, Egyptian authorities arrested several prominent revolutionary activists, including Alaa Abdul-Fattah and Ahmed Maher after they had participated in a protest against the new demonstration law, which places strict limits on the freedom of assembly.