A Muslim woman and a civil rights group in the Midwest U.S. city of Chicago have filed a lawsuit, following a strip search of the woman at Chicago's O'Hare Airport. The American Civil Liberties Union calls the search "discrimination."

Last November, 22-year-old Samar Kaukab was about to fly home to Columbus, Ohio, from a conference in Chicago, when she was stopped at a passenger screening checkpoint at O'Hare Airport. She underwent a 30 minute search she calls embarrassing and unnecessary.

"I was so frightened that I could barely speak. I kept wondering why this was happening. I feared I might be detained," she said. "I feared that something else might happen. Would I be subjected, for example, to a body cavity search? I also felt embarrassed and humiliated."

Ms. Kaukab said she passed through the airport metal detector without triggering the alarm, but was asked to step aside, while a security guard passed an electronic hand-wand over her. The guard asked Ms. Kaukab to remove her hijab, or headscarf. She cited her religious practices in declining to remove the hijab at the security checkpoint, but agreed to remove it in a private area in front of female guards.

Ms. Kaukab said two female guards searched her in a private room. They ran their fingers through her hair, and touched her neck, chest, armpits and legs.

The American Civil Liberties Union office in Chicago is representing Ms. Kaukab in her lawsuit against Argenbright Security, which employs the airport screeners who searched her. She is also suing the Illinois National Guard, which also provides security at the airport.

"Forcing a young woman like Miss Kaukab to go into a small room and put their hands in her pants and under her bra after she has already gone through an X-ray machine and failed to alert any signal of wrongdoing, does absolutely nothing to make the American public safer," said Charles Peters, a lawyer for the American Civil Liberties Union. "What makes the public safer is acting on legitimate security concerns, not prejudice."

Ms. Kaukab says she can think of no reason why she was searched other than her ethnicity. She is a U.S. citizen, born in this country to Pakistani parents. Her lawsuit seeks unspecified monetary damages, and a court order to force security firms to train guards, so they will not base searches solely on a person's religion or ethnicity.

Spokesmen for Argenbright Security and the Illinois National Guard say they cannot comment on the lawsuit, until they have a chance to review it. Argenbright provides security to 17 major U.S. airports. The company says ethics is among the topics covered during screeners' training.