Human Rights Watch says Hamas police have prevented some 20 people from demonstrating in solidarity with the Egyptian protesters who are demanding President Hosni Mubarak's ouster.
The New York-based group says the demonstrators gathered Monday in central Gaza City when the police came to stop them.
HRW says police detained six women and roughed some of them up during questioning. Hamas police had no immediate comment.
Gaza's Hamas rulers have issued no official comments on the Egyptian turmoil but officials have privately said that change in Egypt could benefit Hamas by lightening the Gaza blockade.
Hamas' rivals in the West Bank's Palestinian Authority see Mubarak as an ally and also squelched a pro-Egypt protest this week.