News reports are coming in that the suspect is in custody, having been shot.
In the meantime, another TSA agent, aged 40, has been killed, and three other TSA officers have been taken to hospital. One of those officers is said to be in critical condition.
The 40-year-old TSA officer was declared dead at Harbor-UCLA Medical Center at 11 a.m.
The shooter was another TSA officer who appeared to take a gun out of a bag and start shooting at random. He was standing at a screening checkpoint.
People in the crowd heard the shots and starting running for cover. That happened around 9.20am, says San Francisco's ABC 7 local news.
An original report said the shooter was the TSA officer who died, but that is not true.
LAX police fired on the shooter and he was taken into custody but his exact condition is not known.
"It never stops does it?" says San Francisco resident Katie Adler. "The last thing we suspected would happen would be that those who are working to protect us, would be the ones to turn on us."
As a precaution, law enforcement agents are sweeping Terminal 3 at LAX and several law officials are wearing heavy weapons around the area in an attempt to avoid a copycat occurrence.
Update: ABC News has now been told that the initial ID of the shooter at LAX is Paul Ciancia
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Source: ABC 7 News