A car bomb exploded in Iraq's holy city of Najaf on Saturday, killing four Iranian pilgrims a day before a national election, officials said, Reuters reported.
The explosion gutted at least two tour buses parked at a garage near the revered Imam Ali shrine, which draws millions of Shi'ite Muslim faithful from Iraq and Iran each year.
Louay al-Yassiri, a member of the local provincial council, said that in addition to the Iranian pilgrims killed, the blast wounded seven people, including three Iraqi police.
At least 45 people have been killed over the past few days as the election campaign drew to a close, some of them members of the security forces who were voting early.