Iraqi fighters fired several mortars or rockets at the U.S.-led administration headquarters in the Iraqi capital Baghdad Tuesday, wounding at least four people in the second attack on the compound in as many nights. The Pentagon said three of the wounded were from the U.S.-occupation forces, although it was not known if they were military or civilian. An Iraqi guard at the scene said three explosions hit the compound itself, one of Saddam Hussein's former palace complexes, but a U.S. army spokesman in Baghdad could not confirm that. Earlier, U.S. troops in Humvees with powerful spotlights sped to an area along the nearby Tigris, where gunfire was heard. "There were a lot of soldiers running around, there was a lot of panic. I haven't seen any injured people," said Mohammad Shikri, the Iraqi guard at the complex. Journalists were prevented from entering the area. **Bomb Kills U.S. Soldier as Spain Recalls Staff in Iraq*** A roadside bomb killed a U.S. soldier in Baghdad and one of Washington's chief allies, Spain, said it was recalling some embassy and other staff Tuesday in fresh setbacks to U.S. efforts to bring calm to Iraq. The U.S. Army said a soldier was killed and two were wounded when their vehicle ran over a bomb planted on a road, the latest in a string of attacks on U.S.-led forces occupying the country. In the northern city of Mosul, five rocket-propelled grenades were fired at a hotel used as a U.S. military compound but no one was hurt. Also in Mosul, gunmen killed a second Iraqi judge in two days, police said. The first was in southern Iraq. Spain, a key political ally of the United States in the war that ousted Saddam Hussein in April, said Tuesday it was recalling some civilian staff from Iraq for consultations. Prime Minister Jose Maria Aznar said those being recalled included some embassy staff as well as Spaniards working with the U.S.-led Coalition Provisional Authority running the country. A diplomat at the Spanish Embassy in Baghdad said Madrid had taken the decision after last week's bombing of the Red Cross, one of a series of attacks that killed 35 people and wounded 230. Most foreign aid workers have already left Iraq. An official with the U.S.-led coalition dismissed suggestions Spain's decision showed the resolve of U.S. allies was cracking under the strain of near-constant attacks. "Spain continues to be an active and valued member of the coalition," said the official, who declined to be identified. **PHOTO CAPTION*** US humvees enter the heavily guarded main entrance of the headquarters of the US-led coalition following several explosions near the compound in Baghdad. (AFP/Marwan Naamani)