The Palestinian Islamist (Muslim political) movement HAMAS (Harakat al-Muqawamah al-Islamiyyah, "Islamic Resistance Movement") marked the twenty-third anniversary of its founding this week with a massive rally in Gaza City which was attended by tens of thousands of its supporters. The rally shows that the movement remains an influential player in Palestinian politics despite its political and military setbacks since coming to power in early 2006. HAMAS has governed the Gaza Strip since defeating its chief political rival, the Fatah movement, which was founded by the late Yasir 'Arafat, during the first half of 2007 and driving them from Gaza. HAMAS and Fatah fought a short but bitter and bloody war in Gaza, with a reported Fatah coup attempt being preempted by HAMAS.
The movement has come under increasing criticism from small transnational jihadi-takfiri groups operating in the Gaza Strip such as Jama'at al-Tawhid wa'l Jihad fi Bayt al-Maqdis (Group of Absolute Monotheism and Struggle in the Holy House/Jerusalem) and Jama'at Ansar al-Sunnah fi Aknaf Bayt al-Maqdis (Group of the Prophetic Tradition's Supporters in the Shadow of the Holy House/Jerusalem). These small groups likely have fluidity in membership, which photographs and primary source materials I've collected suggests.
My post, with lots of artwork, from last year about HAMAS' 22nd anniversary can be viewed HERE.