American forces clashed with Iraqi fighters in Fallujah on Friday and stood ready to strike at a Shiite leader in Najaf. A hospital official told Reuters 15 Iraqis were killed and 20 were injured in overnight clashes that erupted in Fallujah just hours after America's top general said truce talks could not go on for ever and more military force might be necessary. General Richard Myers, chairman of the Joint Chiefs of Staff, said Paul Bremer, the chief US civilian official in Iraq, was using "multiple channels" in talks to pacify Fallujah and avoid fighting in Najaf, where supporters of anti-U.S. Shi'ite leader Moqtada al-Sadr control the city center. U.S. warplanes attacked targets in Fallujah, and a U.S. armoured vehicle was destroyed in the fighting, witnesses said. **Danish businessman kidnapped*** A Danish man is likely being held captive in Iraq, Denmark's Foreign Ministry said Friday. The foreign ministry did not give more details or identify the missing man, The AP reported. "A Danish national likely is being held back in Iraq," the ministry said in a statement. "No Iraqis or Iraqi groups have contacted Danish authorities." Danish public television DR-1 reported that he was a businessman in his 30s and working on a sewage project in Iraq. The man was traveling from the southern Iraqi city of Basra to Baghdad when he was taken captive in Tadji, DR-1 added. **Rumsfeld surprised by high death toll*** Meanwhile, US Defense Secretary Donald H. Rumsfeld said Thursday that the death toll of American soldiers in recent weeks was higher than he had expected, acknowledging a change in plans as he announced thousands of soldiers won't return home as early as promised. Rumsfeld described a decision to keep some 20,000 soldiers inside Iraq longer than originally planned, telling reporters at the Pentagon: "I certainly would not have estimated that we would have had the number of individuals lost that we have had lost in the last week." **PHOTO CAPTION*** US troops guarding Iraqi prisoner. (AFP/USMC/File/Jose E. GuillenJose)