Iraqi authorities say they will be sealing the country's land borders for five days during a major Shi'ite religious festival next week. All border posts will be closed from February 17-22, which coincides with the height of Ashura, when tens of thousands of Shi'ite Muslims go on pilgrimage to the holy cities of Najaf and Karbala.
Last year, several suicide bombers attacked pilgrims at the Ashura commemorations, and killed more than 170 people.
Iraqi officials say the border closing is a security measure, but they did not link it directly to the religious observance.
The borders were also closed for several days prior to last month's election, as part of the unprecedented security crackdown that accompanied the poll.
Meanwhile, a car bomb exploded in a busy area of central Baghdad just after a U.S. military convoy passed by. The blast in Tahrir Square killed at least two Iraqi civilians, and wounded several more. The bomb was apparently detonated by remote control.
And in eastern Baghdad, gunmen attacked a senior representative of the Grand Ayatollah Ali Al-Sistani, the country's most senior Shi'ite religious leader. The cleric, Sheikh Ammar al-Helali, was wounded but survived the attempt on his life.
About 50 kilometers south of the city, on a road near the town of Suwayrah, police reportedly found the bodies of 20 people who appear to be victims of an ambush. Most of the men are believed to be truck drivers working for the Iraqi Trade Ministry, plus several Iraqi police and soldiers assigned to protect their convoy.
Reports indicate that the attack may have happened two days ago, with the bodies left to decompose in their charred vehicles. It is not clear why it would have taken so long for authorities to discover them. An Interior Ministry spokesman contacted by VOA said he had no information about the incident and could not confirm the number of casualties.
The Associated Press Television News received a videotape of masked gunmen shooting four men who had identified themselves as Iraqi policemen. It is not clear when or where the video was made. Iraqi security forces have been the target of repeated attacks. Suicide bombings aimed at the police and army have claimed the lives of nearly 50 people, including women and children, this week.