House Republicans are demanding information from the Department of Homeland Security about immigrants who win access to the U.S. by falsely claiming they are asylum seekers afraid to return to their home countries.

In a letter sent Monday to Homeland Security Secretary Janet Napolitano, a copy of which was obtained by the Washington Examiner, Rep. Jason Chaffetz, a top Republican on the House Oversight and Government Reform Committee, questioned whether illegal immigrants were being instructed on how to beat the immigration system by falsely claim they are in the U.S. to seek political asylum.

Immigrants are allegedly learning to claim they face a "credible fear" of persecution at home so that U.S. officials can not immediately expel them. Thousands of such cases have been reported along the U.S.-Mexico border, New York City and other parts of the U.S.

Homeland Security is expected to receive nearly 29,000 asylum requests this year from immigrants arriving from Mexico, El Salvador, Honduras and elsewhere, a House Oversight and Government Reform subcommittee revealed in July. That's a 434 percent increase in such requests over the past five years, said Chaffetz, R-Utah, who chairs that subcommittee.

Chaffetz asked Napolitano to provide the number of asylum cases being investigated for fraud as well as the number of lawyers successfully prosecuted for aiding asylum fraud.

House Judiciary Committee Chairman Bob Goodlatte, R-Va., also asked for information on asylum from last week, saying he was concerned that “credible fear” is being “exploited” by illegal immigrants to gain entry into the U.S.

According to reports, many of the asylum seekers are not detained and do not show up at later court hearings regarding their asylum requests.

Chaffetz wants Napolitano to provide all documents “describing the percentage of asylum seekers who do not appear at their scheduled immigration court proceedings.” He also wants to know how much bonus money has been paid to the department’s asylum officers over the past five years.

The Chaffetz letter gives Napolitano until Sept. 9 to provide the information.