Federal agents conducted more than 20 raids yesterday across southern California, targeting the "birth tourism" industry.

Birth tourism is when people from other countries - often wealthy Chinese nationals - pay exorbitant fees - sometimes up to $80,000 - to travel to the U.S. and have their baby here, so that the child will be an American citizen.

William La Jeunesse reported on "America's Newsroom" that the raids were looking for evidence against companies that advertise this service on the Internet.

La Jeunesse reported that the companies offer coaching to people on how to lie to obtain a U.S. visa and how to dress to conceal their pregnancy at the airport.

In return, the baby will get a U.S. passport, birth certificate and a social security number. The parent gets permanent legal residency in the U.S. when the child turns 21.

"It's perfectly legal to have a child born in the United States," DHS special agent Claude Arnold explained. "What is illegal is lying about your reasons to come to the United States, essentially committing visa fraud."

La Jeunesse reported that one operation in Irvine, California, provided birth tourism services to 400 women in two years.

"It's essentially citizenship for sale," Jessica Vaughan, with the Center for Immigration Studies, said. "Something that Americans hold very dear and cherish is just being essentially purchased."

La Jeunesse said that the kicker is that once the women enter a hospital, they often tell hospital admission officials they're indigent, which ends up sticking U.S. taxpayers with the bill.

FoxNews.com reported:

Birth tourism is big business. An estimated 40,000 babies are born to couples posing as tourists each year. The U.S. is one of the few countries in the world that automatically grants citizenship to any child born here, regardless of the parents’ nationality. While it is not against the law, lying to obtain a visa to enter the U.S. under false pretense is illegal.  Companies offering to help foreign nationals give birth in the U.S. operate openly on the Internet, promising a U.S. passport, birth certificate and Social Security number for their newborn. Prices range from $8,000 to $80,000, depending on the services. Wealthy couples from China, the Middle East, Africa and South Korea predominate the trade.

Watch more above.