SEUZ - Hundreds of drivers of Suez-bound mini buses launched a strike Saturday in Cairo to protest against the brutal attack by a Government official against one of their colleagues, stranding thousands of commuters. In the absence of these privately-owned buses, which constitute the backbone of inter-provincial transport, thousands of commuters were stranded in Cairo and could not travel to Suez, eye witnesses said. The drivers are protesting against the beating of one of their colleagues by a Government official during a dispute over fare earlier in the day, the witnesses said. The striking drivers blocked entrances of el-Marg el-Gadida depot on the outskirts of Cairo, where hundreds of mini- buses stood idle during the day. No Government official was available for an immediate comment.