Free Airline tickets - new scam

Hello everyone. In the past few days I've gotten 4 or 5 calls from area codes 213 (Los Angeles, CA) and 559 (greater Fresno area, CA). Most have been hang ups, but one, claiming to be from United Airlines, had two free tickets for me. I laughed so hard I scared the poor guy and he hung up. Checking the number, there were complaints indicating it was a Southwest scam. So essentially, they are claiming to be from airlines. I researched the rest of the numbers and they were all the same scam.

What I've been doing lately when I get these is pick up and say the following:
"Intercept. Enter you access code."

Typically there is a brief pause followed by a hang up.

(Every now and then I'll answer: "Hey Scammer! What's happening?" They get so hostile at that. LOL)