The prime minister, Nouri al-Maliki, announced on Wednesday that Bashar Sabawi Ibrahim Hassan al-Tikriti was arrested with the assistance of Lebanese police.
However, the announcement did not say when exactly al-Tikriti was arrested or what for.
"Bashar Sabawi al-Tikriti is an important element on the most-wanted list due to his ugly crimes against the Iraqi people after the fall of the former regime," the announcement said.
His father, Sabawi, was arrested in February 2005 on the Syrian border on charges of funding the rebellion against US-led occupying forces and testified in the trial of Saddam Hussein, his half-brother, and his brother, Barzan, on Monday.
It was unclear whether al-Tikriti was extradited. The announcement did not offer any other details about the arrest or about al-Tikriti's background and age