MAY 6--A Transportation Security Administration screener is facing an assault rap after he allegedly beat a co-worker who joked about the size of the man's genitalia after he walked through a security scanner.

The May 4 confrontation involved Rolando Negrin, 44, and other TSA employees who had previously taken part in a training session at Miami International Airport, according to these Miami-Dade Police Department reports. Negrin, pictured in the mug shot at left, and his co-workers had been training with new "whole body image" machines--the controversial kind that provide very revealing images of a traveler--when Negrin walked through the scanner.

"The X-ray revealed that [Negrin] has a small penis and co-workers made fun of him on a daily basis," reported cops. Following his arrest, Negrin told police that he "could not take the jokes anymore and lost his mind." After work Tuesday evening, Negrin confronted fellow TSA screener Hugo Osorno in an airport parking lot. Negrin wanted to "resolve a problem," and get Osorno, 34, to "finally respect him."

Instead, Negrin allegedly pulled out a police baton and began striking Osorno, while demanding an apology. A witness told cops that Negrin told Osorno, in Spanish, "Get on your knees or I will kill you and you better apologize." When Negrin, wearing his TSA uniform, arrived for work yesterday, he was arrested on an aggravated battery count and booked into the Miami-Dade lockup. Osorno, police reported, suffered "bruises and abrasions on his back and arms" during the attack.