The United States will pay no ransom for the release of American citizens reported kidnapped by Iraqi militants, President George W. Bush said on Tuesday. "We of course don't pay ransom for any hostages, what we will do of course is use our intelligence gathering to see if we can't help locate them," Bush told reporters. "We will bring these people to justice, we will hunt them down along with our Iraqi friends and at the same time spread democracy," he said.An Iraqi militant group has threatened to kill a U.S. security consultant unless Washington frees all Iraqi prisoners, according to a video aired by Al Jazeera television. Another American is among a group of four Christian peace activists seized by gunmen in Iraq. Jazeera said the militants were demanding the U.S. government pay compensation to Iraqis affected by military offensives led by U.S. troops in Sunni Muslim-dominated Anbar province.