American Airlines has fired a trainee who was confirmed to be on TSA's "no-fly list" after he was accused of calling in bomb threats to other airlines. NBC's Tom Costello reports.

A flight attendant trainee for American Airlines has been fired after the airline discovered he is on the government's "no-fly" list for making several bomb threats against United Airlines – a former employer.

Despite clearing a background check without any warning bells going off, Patrick Cau was discovered to also go by the name of Patrick Kaiser, the identity on the “no-fly” list.

Cau, 40, allegedly called in eight bomb threats to United Airlines between October 2012 and January 2013, according to an 18-page plea agreement filed in federal court in California. Cau is expected to plead guilty to the charges next week.

U.S. District Court of California A flight attendant trainee for Fort Worth-based American Airlines is off the job and on the Transportation Security Administration's "no-fly" list after pleading guilty to making several bomb threats to United Airlines.

Court records show Patrick Cau admitted to calling in eight bomb threats all targeting United Airlines flights while he'd been in training to be a flight attendant for competing American Airlines

The court documents show that Cau called 911 using payphones in Los Angeles, New York City, Las Vegas and Seattle to claim a bomb was on a United flight. At least six of the threats were for flights between Los Angeles and London.

United said it lost about $268,000 in canceled and delayed flights due to Cau’s threats.

United Airlines confirmed that Cau was previously employed by the company, but could not provide further details as to why his employment ended because of the ongoing investigation, United spokesman Christen David told NBC News.

American removed him from the training program in Fort Worth, Texas, back in May. The airline sent an email to employees Tuesday to explain the situation.

Cau could serve a maximum of five years in prison and has agreed in his plea deal to pay $250,000 in restitution to United.