Rehan Motiwala

Rehan Motiwala hugs his father Rafiq after arriving at LAX. (Wally Skalij / Los Angeles Times / June 28, 2013)

WASHINGTON -- For two weeks, Rehan Motiwala, a 29-year-old medical student from Pomona, sat stranded at the Bangkok airport, sleeping for 10 nights on a roach-infested mattress in a dank, windowless detention room reserved for deportees.

Motiwala, a U.S. citizen, wanted to return to his family in Southern California. But earlier this month, as he traveled from Jakarta, Indonesia, to LAX, airline staff in Bangkok refused to issue him a boarding pass for his connecting flight. U.S. and Thai officials told him that he could not travel but offered no explanation, leading him to believe he'd been placed on the U.S. government's secret no-fly list.

After dozing on benches and wandering the airport terminal for four nights, Motiwala was told that a Justice Department official had arrived from the United States to question him. When he declined to answer questions without a lawyer present, U.S. officials left him in the custody of Thai authorities, who tossed him into a detention center in the bowels of Suvarnabhumi Airport.

"They treat you like an animal," Motiwala said in a phone interview.

Motiwala's travel nightmare ended Friday morning when he was finally granted permission to fly out of Bangkok. But his ordeal underscores the mystery that continues to surround the no-fly list 12 years after its creation. U.S. officials refuse to say who's on the list or why, arguing that any explanation could alert potential terrorists about who is being watched.

In 2010, after the American Civil Liberties Union challenged the no-fly list, the government said it had created a procedure to bring American citizens and permanent residents stuck overseas back to the United States regardless of their no-fly status. The goal was to "quickly resolve the travel issues of U.S. persons located abroad," a senior FBI official told a federal court at the time.

Cases like Motiwala's show how the government has failed to carry out that policy, civil rights groups say.

"The onus is really on the government to facilitate the return of this person," said Fatima Dadabhoy, an attorney with the Council on American-Islamic Relations in Los Angeles, which is representing Motiwala. "Whether or not they're on the no-fly list, they can still come home."

The group says it is handling at least two other cases of U.S. people from the L.A. area who have been barred from flying and are marooned abroad.

Although travelers can petition to be removed from the no-fly list, civil liberties advocates say the Department of Homeland Security's redress process is so opaque that the only way to know if you've been cleared is to attempt to fly again.

A federal appeals court in Oregon last week heard arguments in a case brought by the ACLU, whose clients are suing the government to either be removed from the list or told why they are on it.

State and Justice Department officials in Washington offered no information about Motiwala's status, saying they couldn't discuss specific cases. The American Embassy in Bangkok, whose consular officers were in contact with Motiwala during his detention, declined to comment.

A Justice Department official said about 20,000 people were on the no-fly list as of October, including between 500 and 1,000 American citizens. Experts say cases of travelers being stuck in an airport are extremely rare.

Motiwala, whose parents are of Pakistani origin, was not told why he might be on the list. A likely possibility, however, is his contact with Tablighi Jamaat, a conservative Muslim missionary movement based in South Asia.

He took leave from medical school last year, traveled to Pakistan to visit relatives and went on to Indonesia to work with the group, members of which go around the world proselytizing for Islam.

Tablighi Jamaat is widely regarded as peaceful and apolitical, and claims millions of followers, but U.S. and European law enforcement officials have raised questions about possible connections to radical Islam.

John Walker Lindh, an American who converted to Islam, met Tablighi missionaries in California before joining the Taliban to fight U.S. forces in Afghanistan. British security officials allege that two of the suicide bombers who attacked the London transit system in 2005 had attended a Tablighi Jamaat mosque.

Motiwala first heard of the movement when he arrived last year in Karachi, the Pakistani mega-city where his family members live. Inspired by the Tablighis' devotion, he began attending their meetings, improved his Urdu language skills, grew a beard and shed his Western clothes for a Pakistani shalwar kameez, a long tunic.

"They were very welcoming," Motiwala said. "We would ask people to come pray at the mosque, talk about the greatness of God, sit in gatherings and listen to prayers."

Motiwala's parents said he wasn't particularly religious as a child. Born in Anaheim, he grew up in West Covina and Pomona with three brothers, including a twin. He attended UC Irvine, graduating magna cum laude in 2007 with a degree in neurobiology, a university spokeswoman said.