Unknown assailants barged into the headquarters of the Muslim Brotherhood's Freedom and Justice Party in Manial district near downtown Cairo on Friday and damaged its main gate, media reported.
Security forces and policemen arrived at the headquarters after the attackers had left.
A march grouping hundreds of anti-Brotherhood protesters arrived on Friday noon at the headquarters in a demonstration several political powers had called for after supporters of the Brotherhood assaulted media workers and protesters last Saturday in the same place.