Iraqi authorities say Brigadier General Musa Hashim and his entourage was traveling in a convoy when the blast occurred.
Hachim was director of intelligence and counterterrorism operations in Kirkuk.
In other violence, a suicide car bomb exploded in Al-Dhuluiyah, 90 kilometers north of Baghdad, killing five members of an Iraqi security patrol.
Iraqi Prime Minister Nuri al-Maliki was expected to present a national reconciliation plan to parliament on June 25.
The plan reportedly sets out to remove powerful militias from the streets, open a dialogue with insurgents, and review the status of purged members of Saddam Hussein's Ba'ath party.
(with material from AP, dpa, Reuters)