Current security cutbacks contain left the Los Angeles International Airport weak to terrorist attacks, according to a letter from an airport police union calling for a restoration of the safety events.

The letter, released Tuesday, is from Marshall McClain, leader of the Los Angeles Airport Peace Officers Association, to Los Angeles Airport Police Chief George Centeno. The letter says that because of cost-cutting reduction in training, the deployment of traffic control officers and security in the central terminal, the airport is "more susceptible to a terrorist attack than at any time since 9/11."

Gina Marie Lindsey, the administrative director of Los Angeles World Airports who is also copied on the letter, said in a statement Tuesday that "there is no proof to support" McClain's allegations, note that the airport police budget "has greater than before annually since 9/11 and, from previous fiscal year to this year, it increased nearly $3.4 million."

Lindsey's report also emphasized the airport's security, noting that "LAX remains one of the safest airports in the world and one of the safest areas in Southern California due to LAWA's ongoing commitment to staff train and equip Airport Police."

Meanwhile, McClain's letter identify the 3 most likely attack scenarios as determined by a Rand Corporation study of airport security at LAX in 2004: a big truck bomb, a curbside car bomb and a luggage bomb.

The letter, dated June 8, also calls notice to the lack of permanent checkpoints at the airport's six entrances as optional by the Rand organization in 2006 "to decrease the risk of car-bomb attacks."

"Not only has the plan not advanced beyond the design phase, the random checking of vehicles entering the has been very much curtailed in current months," McClain writes.

Nancy Castles, a spokeswoman for LAX, told CNN Tuesday that the fixed checkpoints optional by Rand "weren't implementable," saying that because of the short road leading into the airport, traffic would be backlogged into the major thoroughfare nearby LAX.

Instead, Castles noted, the airport worked in conjunction with engineering students at the University of Southern California to expand a randomized checkpoint system that's determined by computer.

The programs determine the number and location of checkpoints on some given day based on the number of officers obtainable to man them, she said. "Randomization and unpredictability is a key factor in keeping the terrorists unbalanced so they can't size you up and attack you," Castles said. "It is so effective that airports across the US are adopting this technique."

McClain, for his part, points out that since 1974, the airport has been the place of 2 bombings, 2 attempted bombings and one gun attack. "There is no cause to believe LAX is no longer a good-looking aim," he writes in urging Centeno, Lindsey and other airport and city official to "review and reverse new decisions that have considerably reduced LAX's ability to deter an attack."

The letter too needs an "urgent meeting" with Centeno to talk about the security measures, however, as of Tuesday, no meeting had been listed, McClain told CNN -- an allegation Castles disputed.

The LAAPOA represent additional 450 airport police officers and fire workers, according to its website. LAX is the world's 7th busiest airport in terms of passenger traffic, according to 2009 statistics from the Airports Council International.