A government inspector general will investigate reports of fraud and sloppy procedures within the U.S. Citizenship and Immigration Services, the agency's new director said Tuesday.

The allegations range from employees skipping required fingerprint checks on applicants and issuing duplicate green cards, to more serious accusations of bribery and undue influence by foreign governments. Many of the complaints originated with a whistleblower who took them to Sen. Charles Grassley, R-Iowa.

In a meeting with reporters, USCIS Director Emilio Gonzalez said he forwarded Grassley's complaints, raised in a letter last month, to the Department of Homeland Security inspector general, who agreed to investigate. Citizenship and Immigration Services is part of DHS.

But Gonzalez, who was confirmed by the Senate in December, downplayed some of the complaints and dismissed others.

"Coming to the U.S. is probably the greatest prize in the world and people will do whatever it takes to get here," Gonzalez said. "So that there's fraud out there? I assume there is. Is this something that's rampant and something we don't have a handle on? I think that's probably going a bit too far."

Gonzalez also disputed Grassley's claims of sloppy procedures including skipped fingerprint checks, duplicate residency cards, missing files and failures to serve notices to appear on criminal aliens. "I do not think that those allegations are correct," he said.

Grassley's letter raised concerns that criminals or potential terrorists could take advantage of the problems. He said his office had heard of bribery of employees and of high-level employees being paid by foreign governments to grant or deny immigration benefits to nationals of that country.

The senator said he was concerned that Gonzalez's agency was focused on "customer service" to the detriment of homeland security matters.

The agency is under pressure to get through a backlog of immigration applications, but Gonzalez insisted security concerns come first. He said he wasn't aware of employees getting rewarded for fast processing of applications with days off and other benefits, as alleged by the whistleblower, Michael Maxwell.

Maxwell resigned last month as director of the Office of Security at U.S. Citizenship and Immigration Services and sought whistleblower protection, claiming retaliation for telling lawmakers of security problems.

"I genuinely believe you can have the backlog reduction plan and you can have security," said Gonzalez. "The minute you can't have them both then you err on the side of security."

Gonzalez also said his agency would be ready to handle an influx of new applications if Congress approves a guestworker immigration program. That was a turnaround from his confirmation hearing in October, when he said the existing system wouldn't be able to handle such a program.