One US soldier was killed and two others were injured during an ambush in northern Iraq, the U.S. military said Friday. The incident occurred at about 11 p.m. Thursday when unknown attackers fired a rocket-propelled grenade at the soldiers' vehicle in the city of Kirkuk. Also, a mortar blast in a market north of Baghdad, killed Thursday night eight civilians. The blast occurred about 9 p.m. Thursday at a market in Baqouba, about 50 kilometers north of Baghdad. Eight civilians died and another 18 were wounded, the US Army said, according to The AP. In the north, meanwhile, eight US troops were injured when their convoy was ambushed with roadside bombs and small arms fire in Mosul. At least two Iraqi bystanders were also wounded. The commander of U.S. forces in Iraq, Lt. Gen. Ricardo Sanchez, warned he would use whatever force necessary to defeat those who attack American soldiers. Meanwhile, Secretary of State Colin Powell said Bush administration planned to set a six-month deadline for an Iraqi constitution with a view to elections in 2004. "We would like to put a deadline on them," Powell told the New York Times. "They've got six months. It'll be a difficult deadline to meet, but we've got to get them going." He raised the option that the Iraqis themselves could shortly decide on a timetable, adding that the US government has asked Iraqi leaders to estimate how long it would take them to prepare a constitution and hold elections. According to Powell, the constitution will determine whether Iraq should be governed by a presidential or parliamentary system and clear the way for elections and the installation of a new government in 2004. **PHOTO CAPTION*** US Secretary of State Colin Powell, Feb. 14, 2001. (Photo by Aladin Abdel Naby/Reuters)