A foreign investor visa program now at the center of a federal investigation has long been the target of criticism by many who say it does little to help the U.S. economy and allows rich foreigners to buy their way to the front of the immigration line.

The visa, called "EB-5," has an annual cap of 10,000, but has struggled most years to attract even half of that number because of red tape and a lack of awareness internationally about its existence, various government reports on the program have found.

News that U.S. Citizenship and Immigration Services director Alejandro Mayorkas is under investigation by the Homeland Security Department's inspector general's office in connection to his possible role in helping a company secure an EB-5 visa for a Chinese executive has refocused attention on the visa program.

Last year, EB-5 applications hit a record, with slightly more than 6,100. As has typically been the case, China accounted for the vast majority of petitions, with 5,121, according to USCIS.

The allegations against Mayorkas have cast a dark cloud over his nomination by President Obama to be the No. 2 official at the Department of Homeland Security. At a Senate hearing Thursday on his DHS nomination, Mayorkas strongly denied the allegations that he had helped the Chinese executive get the investor visa.

He told the Senate Homeland Security and Government Affairs Committee that suggestions of impropriety on the visa matter were "unequivocally false" and that he had overseen the program "based on the law and the facts and nothing else."

"I have never, ever in my career exercised undue influence to influence the outcome of a case," he said. "I have never based my decisions on who brings a case but rather on the facts and the law."

White House counsel Kathryn Ruemmler sent a letter to the committee stating that the administration has no concerns about Mayorkas' "suitability" for the post. She said the White House followed standard procedures in checking out Mayorkas for the job and urged the Senate to swiftly confirm him.

Latin American countries barely register on the list of nations from which EB-5 applications originate.

Mexico, for instance, accounted for 80 applications last year (of which 56 were approved) followed by Venezuela, with 54 applications and 46 approvals.

Increased investment from China has fueled the demand for the visa, which was established in 1990.

Supporters of the visa say it helps the U.S. economy by attracting capital and creating jobs at virtually no cost to the United States.

USCIS said the program has helped create nearly 50,000 jobs and generated more than $2 billion since its inception.

But critics say it’s hardly a dent in the overall foreign investment in the United States and thus makes little actual improvement to the economy.

Many also take exception to the fact that the elite – who must invest at least $1 million in a new business, or $500,000 for a business in a rural area or one with high unemployment – can fast-track admission to the United States and later qualify for "green cards," or permanent residency. Their dependents also can obtain green cards based on the investor’s status, something not available to most other visa-holders.

“The typical EB-5 recipient is a middle-aged man with a family from South Korea, China or Taiwan,” wrote Charles Lane in an opinion piece in the Washington Post. “The line for U.S. visas is especially long in those countries. You can understand why well-heeled individuals would want to buy their way to the front of the queue. It's harder to understand why the U.S. government would want to favor them.”

Lane added: “Simply put, it is corporate welfare — yet another attempt to subsidize the flow of capital into politically favored channels. The standard objection to EB-5 is moral: The United States should not be in the business of selling the right to live in this country.”

According to an email sent to lawmakers Monday evening, the IG's office said that it initially started investigating the EB-5 visa program last year based on a referral from an FBI analyst in the counter intelligence unit in Washington.

In the email detailing the case, the IG's office said "at this point in our investigation, we do not have any findings of criminal misconduct." The email does not specify what criminal violations it is investigating.

Mayorkas, who came to the United States from Cuba with his family in 1960, has been the clear front-runner for the No. 2 spot at the Department of Homeland Security. And, if confirmed by the Senate, he could likely run the department, at least temporarily since current director Janet Napolitano is stepping down.

Mayorkas' confirmation hearing on Thursday played out with an empty bank of chairs for the committee's Republicans. Sen. Tom Coburn of Oklahoma, the ranking Republican on the panel, released a statement saying he wouldn't participate because it would be unfair to do so until the allegations are resolved and there is no pending investigation.

"We believe the committee must wait until these allegations against Mr. Mayorkas are resolved before deciding whether to move forward with his nomination," Coburn said.

A Loyola Law School graduate, Mayorkas has a long history in public service, including holding the post of U.S. Attorney for the Central District of California, and commissioner for the California Commission on the Fair Administration of Justice.

The IG’s email said the primary complaint against Mayorkas was that he helped a financing company run by Anthony Rodham, the brother of former Secretary of State Hillary Rodham Clinton, to win approval for an investor visa, even after the application was denied and an appeal was rejected.

“The program is prone to corruption and waste because the investors care much more about their visas than the details of the investment,”  David North, who has written reports on the visa program for the Center for Immigration Studies, a conservative think tank, told Fox News Latino.

“It is also tiny, in terms of the vast flows of additional foreign investment coming to the US. It accounts for maybe six cents out of every additional $100 in foreign investments in the U.S.," he said.

A 2010 DHS report on EB-5 cited a lack of transparency about how visas are awarded or rejected as one of the flaws of the program.

Even operators of the program, the report said, felt that tracking the process of an application and the ultimate decision on it was difficult.

“Neither the applicant nor the Regional Center is able to track the application’s process and it was felt that there was a lack of available information about the specific criteria,” the report said. “Furthermore, Regional Center operators indicated that the adjudication process seemed to vary from case to case with little consistency.”

EB-5 investors have come from countries with whom the U.S. has little or troubled diplomatic relations, such as North Korea, Iran and Syria, USCIS data shows.

The FBI in Washington has been concerned about the investor visa program and the projects funded by foreign sources since at least March, according to emails.

The agency wanted details of all of the limited liability companies that had invested in the EB-5 visa program. Of particular concern, the FBI official wrote, was Chinese investment in projects, including the building of an FBI facility.

"Let's just say that we have a significant issue that my higher ups are really concerned about and this may be addressed way above my pay grade," the official wrote. The FBI official's name was redacted in the email.

Iowa Sen. Charles Grassley, the ranking Republican on the Senate Judiciary Committee, sent the FBI a lengthy letter Tuesday asking for details of its review of the foreign investor visa program and Chinese investment in U.S. infrastructure projects.

Chinese investment in U.S. infrastructure projects has long been a concern of the U.S. government. In September, the Obama administration blocked a Chinese company from owning four wind farm projects in northern Oregon that were near a Navy base used to fly unmanned drones and electronic-warfare planes on training missions.

And in October, the House Intelligence Committee warned that two leading Chinese technology firms, Huawei Technologies Ltd. and ZTE Corp., pose a major security threat to the U.S. Both firms have denied being influenced by the Chinese government.

According to the Inspector General's email, the investigation of the investor visa program also includes allegations that other USCIS Office of General Counsel officials obstructed an audit of the visa program by the Securities and Exchange Commission. The email did not name any specific official from the general counsel's office.

For his part, Mayorkas has come under fire before for his involvement in the commutation by President Bill Clinton of the prison sentence of the son of a Democratic Party donor. Another of Hillary Clinton's brothers, Hugh Rodham, had been hired by the donor to lobby for the commutation. Mayorkas told lawmakers during his 2009 confirmation hearing that "it was a mistake" to talk to the White House about the request.

Hillary Clinton is considered a possible presidential candidate for 2016.

The Associated Press contributed to this report.

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Elizabeth Llorente can be reached at elizabeth.llorente@foxnewslatino.com

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