He then fired on two other uniformed TSA employees and an airline passenger, who all were wounded, as he moved through the security checkpoint to the passenger gate area, authorities said.
He was shot four times, including once in the mouth, by airport police as panicked travelers either hid or fled.
Ciancia has been charged with murder and other counts and faces a possible death sentence if convicted.
Authorities wouldn't comment on Ciancia's current condition.
He was listed in fair condition when he was released from a Los Angeles hospital before he was placed in federal custody two weeks ago.
Investigators have said Ciancia had a vendetta against the federal government and targeted TSA officers but his motive has remained unclear.
