The man suspected of opening fire at
The suspected shooter, identified by police as 23-year-old
The incident Friday began, police say, when Ciancia entered Terminal 3 through the main door, pulled an AR-15 assault rifle out of a bag and "began to open fire."
He then walked up a flight of stairs to the entrance of the security checkpoint, where at least three Transportation Security Administration officers were shot, officials said. One of them, Gerardo I. Hernandez, 39, was killed.
Authorities said Ciancia then entered the airport itself, walking past a candy shop, a newsstand and a bookstore.
The airport police officer and sergeant engaged Ciancia in a brief gunfight near a food court, officials said.
"They hit him multiple times before he went down," one law enforcement source said. A witness said the gunman was wearing a bulletproof vest.
Authorities on Saturday were trying to figure out the motive for the attack.