Four Americans killed by a roadside bomb in Iraq

A roadside bomb exploded Tuesday near a passing convoy of Iraqi security guards and foreign contract workers south of Basra, killing four people, police said.

Capt. Mushtaq Kadim of the Basra Rapid Response Unit said the four dead were Americans. But U.S. diplomatic and military officials in Baghdad were unable to confirm the report, saying only that the victims were not diplomats or soldiers.

Associated Press Television News videotape showed a wrecked SUV at the side of the highway near Zubair, about 30 kilometers (20 miles) south of Basra. British soldiers and Iraqi police blocked off the area.

Although southern Iraq, where some 8,500 British troops are deployed, has been mostly calm since U.S. and British forces occupied Iraq more than two years ago, there has been increasing violence there in the past two months.

Last Wednesday, a roadside bomb exploded near a passing convoy of U.S. diplomatic security guards, killing four Americans.