Story highlights Grand jury indictment shows four people have been arrested in alleged scheme

Indictment says TSA employees allowed drugs to pass through security checkpoints

In exchange for looking other way, screeners received cash, indictment says

Three others are suspected in the 2011 incidents at Los Angeles International

Two current and two former TSA employees have been arrested in an alleged drug and bribery scheme by screeners who allowed large shipments of narcotics to pass through security at Los Angeles International Airport in exchange for cash, federal prosecutors said.

Three other people, suspected drug couriers, are allegedly involved. One is in state custody. A second is expected to surrender on Thursday. Authorities are searching for a third.

According to a 22-count grand jury indictment unsealed Wednesday, the Transportation Security Administration employees took payments of as much as $2,400 to allow suitcases filled with cocaine, methamphetamine and marijuana to pass through X-ray machines at LAX while TSA screeners looked the other way.

The indictment outlines five separate incidents that occurred from February 2011 through July 2011.

TSA employees allegedly conspired with either drug couriers or an undercover operative working with the Drug Enforcement Administration to smuggle narcotics through checkpoints.

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In one incident, two suspects allegedly agreed to have a third suspect bring about 5 kilograms of cocaine in a bag through a security checkpoint manned by one of the TSA screeners. But that third screener failed to follow the instructions and went to the wrong security checkpoint, where TSA officials uninvolved in the scheme seized the bag filled with cocaine.

In the final incident outlined in the indictment, two TSA screeners allegedly conspired with the DEA confidential source to allow about 8 pounds of methamphetamine to pass through a security checkpoint staffed by one of the two screeners. After the drugs made it through security, the suspect allegedly met the confidential source in an LAX restroom to receive $600 in cash, which was the second half of the agreed-upon $1,200 fee.

The U.S. Attorneys Office for the Central District of California says all the defendants were arrested either Tuesday night or Wednesday morning.

If convicted, each of the current and former TSA officials faces potential life in prison sentences.

"Airport screeners act as a vital checkpoint for homeland security, and air travelers should believe in the fundamental integrity of security systems at our nation's airports," said U.S. Attorney André Birotte Jr. in a news release. "The allegations in this case describe a significant breakdown of the screening system through the conduct of individuals who placed greed above the nation's security needs."