Clashes between Hamas and Fatah forces erupted early Friday, wounding at least six people throughout the Gaza Strip, in another setback to a new security plan aimed at halting the wave of violence plaguing the chaotic coastal area and restoring law and order. In the first phase of the plan, an estimated 3,000 police fanned out in Gaza City, taking up positions at main intersections and government buildings. Hamas is angered that Palestinian Authority Chairman Mahmoud Abbas of Fatah has not coordinated the new deployment with them. In one incident, a minibus filled with Hamas gunmen opened fire at a Fatah security force manning a new roadblock. Palestinian medical officials said at least four people were wounded in this exchange. In another attack, gunmen opened fire at the national security building in central Gaza and in the northern Gaza Strip two more were wounded when Hamas gunmen opened fire at their car. Since the Israeli disengagement from Gaza in 2005, the area has experienced a wave of infighting, armed robberies, deadly family feuds and kidnappings. Attempts to halt the violence have failed, and the interior minister in the new Palestinian coalition government, Hani Kawasmeh, has threatened to resign because his plan for restoring security has not been carried out. Hamas and Fatah formed a unity government in March with the aim of restoring calm. The alliance has brought a lull in factional fighting, but crime and violence remain rampant in Gaza.