According to this article in Reuters, NPR is reporting that

U.S. forces near Baghdad found a cache of 20 medium-range missiles equipped with potent chemical warheads.
Citing a top official with the 1st Marine Division, NPR said the BM-21 missiles were equipped with sarin and mustard gas and were "ready to fire."

And separately in the same article:

Maj. Michael Hamlet of the U.S. 101st Airborne Division said earlier that initial tests on substances found at a military training camp in central Iraq revealed levels of nerve agents sarin and tabun and the blister agent lewisite.
"If tests from our experts confirm this, this could be the smoking gun. It would prove Saddam has the weapons we have said he has all along," Hamlet told Reuters correspondent Kieran Murray.

Oh, Haaaaaaaaaaans... Somebody's got some 'splaining to do.