Police said the bomber blew himself up while al-Zawba'i was at a mosque in the courtyard of his Baghdad home and that a car bomb nearby exploded at about the same time.
The attack is reported to have killed at least two people.
Al-Zawba'i, a Sunni, is one of two deputy prime ministers in the government of Prime Minister Nuri al-Maliki.
The attack came one day after a rocket landed meters from the building where al-Maliki was holding a news conference with United Nations Secretary-General Ban Ki-moon.
(AFP, AP, Reuters)
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