Insurgents opened fire on a US patrol in the northern Iraqi city of Mosul tonight, injuring one soldier who later died of his wounds, Lieutenant Colonel Joseph Piek said.
He said the attackers had opened fire on the patrol in a district in southern Mosul on earlier this evening.
Meanwhile Iraqi Shi'ite cleric Moqtada al-Sadr ordered his Mehdi Army today to launch a broad new offensive against US-led occupying forces following a US crackdown on his strongholds in Baghdad and across the south.
The US military claimed new successes in campaigns against Sadr's forces and minority Sunni Muslim insurgents.
Sadr's chief aide speaking from his main base in the holy city of Najaf said that a new phase had begun in a month-long insurgency across Shi'ite southern Iraq.
"We have now entered a second phase of resistance," he said. But US commanders, helped by rival Shi'ite leaders, sound increasingly confident of containing the Mehdi Army.
Tanks flattened Sadr's office in Baghdad's Sadr City district overnight and U.S. spokesman Brigadier General Mark Kimmitt made a hard-to-verify claim that troops killed 35 fighters in the sprawling Shi'ite slum.
US forces, spurred on by mounting irritation with Sadr among Shi'ite elders, have also squeezed the outskirts of Najaf.
With British forces around Basra, they have been taking back key positions such as police stations in a string of towns across Shi'ite southern Iraq. An armoured U.S. column rolled again into the centre of the holy city of Kerbala today.