Mayor Eric Garcetti said at a news conference that the airport police had responded to the gunfire, trailed the man and shot him after he crossed through a security checkpoint as he continued firing the weapon. The authorities did not say whether the gunman had been killed, and the police said one person had been arrested.

 

At least seven people were injured, including six who were taken to the hospital.

 

A federal official said the agent who was killed was standing at an identification checkpoint examining tickets.

 

The Federal Bureau of Investigation has taken charge of the investigation.