Immigrants in the United States illegally are not automatically eligible for asylum on the basis that they are former gang members who risk persecution if they return home, a federal appeals court panel ruled Wednesday.

Three judges from the 9th U.S. Circuit Court of Appeals upheld federal immigration standards that exclude former gang members from social groups that can clearly qualify for protection.

The ruling could affect thousands of immigrants who are fleeing gang-related violence in Central America, immigration experts said.

"We have so many asylum seekers form Central America, and we have a lot of people who are forced to join gangs," said Fatma Marouf, a professor at Texas A&M University School of Law who wrote a brief in the case.

The ruling came in a deportation proceeding against a man from El Salvador, Wilfredo Garay Reyes, who left a gang in his home country and entered the United States illegally in 2001 at the age of 18, after being shot in the leg by a gang leader upset about his defection. Garay sought to stay in the United States under a law that prevents U.S. authorities from sending immigrants to countries where their lives would be threatened because of their race, religion, nationality, membership in a particular social group, or political opinion.

Garay argued that former members of his El Salvador gang constituted a "particular social group," and the gang members would kill him if he returned to El Salvador — possibly by placing a gasoline-filled tire around him and burning it, a method they prefer, he said.

Immigration officials rejected Reyes' claim on the grounds that former gang members do not constitute a particular social group.

The Board of Immigration Appeals said to qualify as a particular social group, there must be evidence showing that society "perceives, considers, or recognizes persons sharing the particular characteristic to be a group."

Garay's proposed group — members of the Mara 18 gang in El Salvador who have renounced their gang ties — was too broad, and there was little evidence society recognized them as a distinct group, the board said. The appeals court panel upheld the decision.