A roadside bomb has killed an Iraqi man as he stepped off a bus in the town of Ramadi, west of Baghdad, just hours after gunmen killed four Iraqi policemen at a checkpoint in the same area.
Three other people were wounded in Monday's bombing.
In northern Iraq, U.S. troops are searching for three American soldiers missing since Sunday, when an Army helicopter plunged into the Tigris River while on a search-and-rescue mission near Mosul. Officials have not announced the cause of the crash.
Meanwhile, U.N. Secretary General Kofi Annan is preparing to announce whether he will send a team to Iraq to explore the possibility of elections ahead of the transfer of sovereignty to an interim Iraqi government in June. The U.N. chief said his announcement could come as early as today.
Iraq's top Shi'ite Muslim leader is demanding direct elections before the transfer of power from the U.S.-led coalition, and his followers have staged huge marches in support of the demand.
The United States says there is not enough time to organize free and fair elections before the end of June.
Both the Bush administration and the U.S.-appointed Iraqi Governing Council in Baghdad have asked the United Nations to study the elections question.
Some information for this report provided by AP, AFP and Reuters.