Authorities in Gaza should halt interrogations, detentions, and harassment apparently aimed at intimidating civil society activists, Human Rights Watch said Monday. "Hamas should respect their rights to freedom of expression and assembly," the group said in a report noting the arrest of youth activist Abu Yazan, who campaigned for Palestinian unity in March. “If Hamas expects to be treated as a responsible governing authority, it should stop persecuting peaceful critics in Gaza,” said Joe Stork, deputy Mideast director at the New York-based rights group. Security forces have repeatedly detained Abu Yazan over the past year. They stepped up interrogations and detentions after he and seven others published a “Gaza Youth Manifesto” in late 2010 that criticized both Israel for the blockade of Gaza and Hamas for curbing freedom of expression. Abu Yazan was also a leader of the March 15 movement, which organized demonstrations against the intra-Palestinian division between Hamas and its rival, Fatah, in the West Bank. “They took all my passwords for my Facebook and Twitter and email accounts, and still haven’t given back my computer or mobile phone” since he returned from France two weeks ago, Abu Yazan says. “I can’t count the number of times I’v been arrested and interrogated,” he says. “More than 10 times since March, at least.” Authorities in Gaza have begun scrutinizing youths who travel to Western countries in recent months, residents of the enclave and human rights groups say. A recent decision blocking eight students from traveling to the United States for university has prevented them from accepting scholarships and prompted local rights groups to speak out. Rawyeh Ash-Shawwa, member of the legislative council and head of the Independent Commission for Human Rights, called on Prime Minister in Gaza Ismail Haniyeh to personally reverse the decision. The education minister in Gaza has cited “social and cultural reasons” for the decision, according to the students and a recent statement by the Palestinian Center for Human Rights. On Monday, Human Rights Watch urged Hamas to overturn the decision. “Hamas should be encouraging young people to seek educational opportunities, not arbitrarily blocking them from traveling abroad to study,” said Joe Stork, Human Rights Watch's deputy Mideast director.