At least three Iraqi protesters were killed when U.S. troops opened fire Wednesday during an Iraqi demonstration outside the main gate of the presidential compound. Minutes after that in southern Baghdad, two US soldiers guarding a filling station were also killed in a hand grenade attack, Al-Jazeera reported. US helicopters arrived at the scene and removed the bodies. Several hundred Iraqis, former employees in Iraqi army, gathered outside the gate and began throwing stones at the guards of the sprawling complex. They threatened occupation forces with bomb attacks if they don't receive their monthly salaries. Gunfire rang over the area in response. Demonstrators began to scatter when the gunfire sounded. Newsmen also retreated under a hail of stones. Military officers inside the compound had no immediate information. The subject of the protest was not immediately known, but demonstrations outside the Republican Palace have been frequent since the coalition capture of the Iraqi capital in April. The demonstration came as U.S. troops intensified their searches in the capital for illegal weapons and supporters of Saddam's regime. Before dawn Wednesday, troops sealed several streets of the Karrada neighborhood, and called residents from their beds to stand in the street as they searched their homes. One man was taken away with his hands bound behind his back. **PHOTO CAPTION*** US troops aim at a crowd of angry protesters outside the US administration offices in Baghdad. (AFP/Ramzi Haidar)