He was thought to have been killed in the first few weeks of the war, and was number five on the list of 55 most wanted Iraqis.
The Pentagon, which is the American military headquarters, has no more information about where he was captured.
Poison gas
He got his nickname because he used poison gas against Kurds who tried to rebel against Saddam.
The US will be very happy if they have captured him, because he might be able to help them find out if Saddam Hussein is still alive, and if so, where he is.
Hear story
Should UK troops still be in Iraq?
Know your world leaders?
Dad's come home from Iraq!
