The pair were released last month after spending five years in jail. Seif recently returned from Paris where he met the outlawed Muslim Brotherhood leader.
It’s unclear why either of the men were arrested, but it’s likely to be just to gather information. Authorities recently banned the two men from holding a press conference.
Seif was picked up at dawn on Wednesday and taken into custody for a couple of hours. Homsi had been released just before Seif was arrested.
Homsi says police searched his house and his father’s house and questioned his son.