Hamas security forces wearing masks and wielding batons and rifle butts forcibly "dissolved" a protest against the "suppression of freedom" in Gaza.
Thursday's rally was staged by Gaza residents and supporters from Egypt decrying the Hamas administration's systemic repression of free speech and imposition of Islamic law in the coastal enclave.
Witnesses say Hamas policemen broke into the hall where the event was being held, cut off electricity, detained journalists, confiscated cameras and mobile phones, and forcibly ejected the protesters. Those who resisted were reportedly answered with batons and rifle butts.
Hamas has routinely incarcerated, kidnapped, maimed and tortured dissidents and political rivals in Gaza over the past five years.
Notably – after Hamas seized control of Gaza – several members of the rival Fatah faction were dragged from their homes and shot in both legs.
It has also stepped up its campaign against journalists who criticize its administration in Gaza in the past year.
Recently, on 9 March, three reporters were attacked by Hamas security forces while covering a mass wedding in Gaza City. The three, who had criticized Hamas, were severely beaten in a nearby playground.
One of the reporters, Sky News stringer Mohammad al-Mashharawi, was detained for several days in an unknown location.
Last year, youth activist Abu Yazan, who has been using Facebook and other social media to call for political freedom in Gaza was arrested for criticizing Hamas.
His group – Gaza Youth Break Out – had published a manifesto that condemned Hamas, Fatah and other Arab political factions, as well as those in Israel. It had called for “freedom and a normal life.”
His whereabouts remain unknown.
During the power crisis that dominated Gaza from January to April, Hamas issued arrest warrants for those who publicly criticized their poor handling of the enclaves' affairs.
At the time, Khalil Abu Shamala told reporters his arrest warrant included accusations from the Hamas-run energy authority that he had blamed them for the energy crisis in Gaza.
It also charged Shamala had "created a rift amongst citizens," as well as "threatening the security of the authority."
Several other dissidents in Gaza who expressed similar sentiments were also arrested.
On 20 April, the United Nations Human Rights Commission charged Hamas has illegally executed at least 18 men since it seized power in the coastal enclave in a bloody 2007 putsch.
Local activists, however, say that number only includes official executions.