Al-Saffar is a member of Prime Minister Nuri al-Maliki's Shi'ite-dominated Islamic Dawa Party.
Unconfirmed reports say he was taken away from his home by several men wearing army camouflage uniforms.
No further details were immediately available.
Earlier in the day, a suicide bombing that targeted a group of Iraqi construction workers killed 22 people in Al-Hillah, a town 100 kilometers south of Baghdad.
At least 44 workers were wounded in the attack.
Police say the suicide bomber, who was wearing a belt packed with explosives, blew himself up in the midst of a group of dozens of workers.
In Baghdad, a triple car-bomb attack at a bus station killed at least six people.
In another incident on November 19, eight people were killed near the restive city of Ba'qubah when gunmen attacked their minibus. The passengers were mainly farm laborers.
The latest incidents come shortly ahead of the arrival in Baghdad of the Syrian foreign minister, Walid al-Muallim.
Muallim is expected to meet with al-Maliki and other senior government officials during his two-day visit.
Violence on November 18 left 53 people dead, including 18 Sunni insurgents killed by U.S. and Iraqi troops in Ba'qubah, 35 kilometers northeast of Baghdad. One of the victims was Ali al-Athab, a member of the political bureau of the Supreme Council for the Islamic Revolution in Iraq (SCIRI). Police also found 23 corpses around the country, including 20 in Baghdad.
The figures for November 18 do not include the reported death of one of five Western security guards kidnapped on November 17. Reports during the day indicated that one of the hostages had been killed and two freed, but those reports were subsequently denied by Iraqi officials.
(compiled from agency reports)
RFE/RL Iraq Report
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