Authorities dug through the rubble for survivors of the blast, which devastated a highway directorate between Tikrit and the northern oil hub of Kirkuk.
Other bomb attacks today -- in Baghdad and at a police checkpoint northeast of the capital -- killed at least four and wounded another 15 people.
The U.S. military said today that one of its soldiers was killed early this morning by a roadside bomb near the capital.
Group Claims To Have Killed Journalist
An Iraqi militant group has claimed responsibility for the killing of Iraqi journalist Sahar al-Haidiri on June 7.
Al-Haidiri, a mother of three who worked for the independent Aswat al-Iraq news agency, was killed in the northern city of Mosul on June 7.
In an Internet statement, Ansar Al-Sunnah said al-Haidiri had "distorted the reputation of the mujahedin."
The Committee to Protect Journalists says it was "outraged" by al-Haidiri's killing.
More than 180 media workers, most of them Iraqi, have been killed in Iraq since the U.S.-led invasion to oust Saddam Hussein began in 2003.
(AP, Reuters, AFP)
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