Los Angeles (CNN)Federal agents on Tuesday raided more than three dozen "maternity hotels" in Southern California where foreign women give birth, allegedly for the sole purpose of having a U.S.-citizen baby, authorities said. The "maternity tourism" sites included apartment complexes in Los Angeles, Orange and San Bernardino counties where authorities believe the businesses housed the foreign nationals about to give birth, federal officials said. Those targeted residences are believed to have catered largely to women from China, who paid $15,000 to $50,000 for lodging, transportation and food, according to a statement by U.S. Immigration and Customs Enforcement. Those fees don't necessarily include medical care, authorities said. Authorities are looking for evidence of bringing in and harboring of undocumented visitors; conspiracy, fraud and misuse of visas and permits; tax evasion and false tax returns; and willful failure to file report of foreign bank and financial accounts, court papers said. "Based on the results of the investigations to date, it appears the women pay cash for prenatal visits and the actual delivery," U.S. authorities said. "As part of the package, clients were promised they would receive Social Security numbers and U.S. passports for their infants, which the mothers would take with them when they left the U.S." Some of the packages included recreational trips to Disneyland, shopping malls and even to a firing range, authorities said. "Any women encountered at the search locations will be interviewed and those identified as potential material witnesses will be directed when and where to report for further questioning," authorities said Tuesday. Investigators weren't expected Tuesday to comment further on the outcome of the raids, said ICE spokeswoman Virginia Kice. In all, authorities obtained warrants for 37 locations and ended up searching more than 50 sites, including consensual searches, Kice said. The purported tourism businesses promoted themselves on the Internet and through social media, authorities said. One firm in Rancho Cucamonga, California, advertised in Chinese and branded itself as "You Win USA Vacation Resort." Operators of that firm couldn't be immediately reached for comment Tuesday. Chinese women have been flocking to the United States to give birth, lured because the country grants American citizenship to anyone born on U.S. soil, CNN Money reported last month. That CNN Money account was cited in an affidavit filed Monday in a federal California court by Homeland Security Investigation agent Eric Blair, who asked a judge for a warrant to search Rancho Cucamonga apartment buildings for large sums of cash and evidence of contraband and a crime. The judge granted the warrant. Read one affidavit . "Perpetrators of visa fraud schemes typically charge $40,000 to $60,000, which is a fee able to be paid by the wealthy in China," Blair stated in court papers. In 2012, about 10,000 Chinese women gave birth in the United States, more than double the 4,200 in 2008, according to Chinese state media. Blair alleged that the birthing houses "will generally advise foreign national clients to fly to tourism points of entry such as Hawaii or Las Vegas and to avoid traveling directly to Los Angeles International Airport. This advice is due to heightened security by (U.S. Customs and Border Protection) officials at LAX based on the volume of fraudulent visas and false statements and entry documents that CPB officials have experienced over the last decade related to birth tourism." One operator of the alleged maternity tourism schemes in California was providing bank statements claiming he had monthly gross receipts of $213,968.79 and an annual income of $1,283,812.74, Blair said in court papers. Those bank statements were provided by an Internal Revenue Service special agent, Blair said. Many of the families want an American child because a foreign passport could be the family's ticket out of China if they grow weary of pollution or food safety scares. President Xi Jinping's widespread anti-corruption campaign has given rich Chinese yet another reason to be on edge. "If things become economically or politically uncertain in one's country of origin, the children have a place to come to," Leti Volpp, a law professor at the University of California, Berkeley, told CNN Money last month. The children can "then sponsor their parents when they turn 21," Volpp said. The desire to leave China is especially pronounced among the wealthy. Almost two-thirds of Chinese with more than 10 million yuan ($1.6 million) in the bank have emigrated, or are planning to, according to a Hurun report released last year. One advertisement for a Hacienda Heights location "claims that the apartments are extremely suitable for expectant mothers and their accompanying families," Blair said in court documents. "The apartment will allow expectant mothers to experience the American lifestyle during their stay." In an interview with CNN Money in February, Felicia He, 27, said she paid tens of thousands of dollars to give birth in California. That interview occurred well before Tuesday's federal announcement of raids. "I started getting ready for the trip around the end of my first trimester," He said. "I asked my friends who have given birth before in the U.S. for a doctor recommendation; then I found a place to stay in the area for a few months, and purchased my plane ticket." He, who gave birth last year, said a U.S. passport for her baby means access to better education opportunities. Foreign status opens the door to exclusive international schools in Beijing, where she lives with her husband, and the option for the child to study abroad for high school and college. There is one catch, though. Getting a U.S. passport for a baby means the child will eventually be responsible for U.S. taxes. CNN's Sophia Yan in Hong Kong contributed to this report.
Authorities get warrants for 37 sites, search more than 50 locations in California . The "maternity tourism" sites are apartment complexes catering largely to pregnant women from China .