Iraqi troops backed by US forces surrounded a town south of Baghdad Sunday following reports that Sunni militants were holding Shi'ites hostage there. But hours later, reporters in Madeen said the troops failed to find any hostages or evidence of the standoff. They say the kidnapping reports may have been grossly exaggerated or the result of tribal disputes and political maneuvering. Several Iraqi government officials gave conflicting comments on the situation in Madeen. Iraqi Prime Minister Iyad Allawi blamed the incident on al-Qaida-linked militants. But a message on an Islamist web site accused the government of fabricating the crisis as a pretext to raid the town. Meanwhile, U.S. officials say three American soldiers have been killed by mortar fire near Ramadi.