A federal investigation is under way into the organization raising funds for a memorial to the Reverend Martin Luther King Jr. in the nation’s capital, according to two people interviewed as part of the inquiry.

The probe of the Washington, D.C. Martin Luther King, Jr. National Memorial Project Foundation is being conducted by the inspector general of the Interior Department, which oversees the National Park Service.

The scope of the inquiry is not clear, but it seems to focus on whether the foundation was obliged to follow federal procurement rules, including competitive bidding and so-called “Buy American” policies favoring domestic sources. The foundation is largely supported by private donations, but it received almost $10 million from the federal government in 2006.

A spokeswoman for the foundation, Rica Orszag, said none of the organization’s leaders were available for an interview for this article.

Word of the investigation comes as the foundation is drawing scrutiny and complaints over its decision to commission a Chinese sculptor, Lei Yixin, to create a statue, made from Chinese granite, to become the centerpiece of the King memorial just off the National Mall in Washington.

Last month, a federal panel that has final approval over such memorials, the U.S. Commission of Fine Arts, said it was “deeply concerned” about the design of the 28-foot-high King sculpture, which shows the civil rights leader emerging from a so-called Stone of Hope.

“The Commission members found that the colossal scale and Social Realist style of the proposed statue recalls a genre of political sculpture that has recently been pulled down in other countries,” the commission’s secretary, Thomas Luebke, wrote. The designers were urged to rework a “confrontational” depiction of King that board members considered “unfortunate and inappropriate as an expression of his legacy.”

While the seven-member arts panel did not object directly to the production of the statue in China, American artists, sculptors, and quarry owners have protested what they call the outsourcing of the King monument.

“I was confused as to why they chose this particular artist from another country and another culture,” a Georgia artist working to rescind the decision, Gilbert Young, said. “My position is, they don’t have the sensitivity, the nuances to complete this statue the way it should be completed. This artist is a member of the Communist Party.”

Mr. Young also criticized the rendering of King. “It is huge. It looks like a dictatorship. It is not in the same spirit of Dr. King,” the artist said.

A South Carolina stone carver, Clint Button, said models of the King statue look a lot like sculptures of Mao that Mr. Lei is well-known for. “You could literally pluck King’s head off and put Mao’s head on. It looks like the same thing,” Mr. Button said.

Mr. Button, who comes from a family of Vermont stonecutters, seems to have triggered the federal inquiry by complaining to the Interior Department in February that American artists and quarries were not given a full and public opportunity to supply the memorial’s central monument. While a public competition for the design of the overall memorial drew 900 entries, there was no public bidding process for the King statue work awarded to Mr. Lei.

“They cherry-picked the best parts off this project and outsourced them,” Mr. Button said.

Mr. Button said he was interviewed about the issue for two hours in March by a special agent from the inspector general’s office. Mr. Young said he was also interviewed.

A spokesman for the inspector general said the office’s policy was not to comment about investigations.

Mr. Button also argued that Chinese carvers would be endangered on the project. “Every picture sent to me of Chinese factories carving … there’s not a single piece of safety equipment there,” he said. “The dust kills people. People will die carving this job.”

A memorial for King was authorized by Congress in 1996. In 2005, with fund-raising for the memorial lagging, Congress used an Interior Department spending bill to give the project $10 million, contingent on the foundation raising an equal sum in new funds from private sources. In March 2006, officials said they had done so. Earlier this year, the foundation announced it had raised $93 million toward its goal of $100 million.

In a recent interview from his home in Changsha, China, Mr. Lei defended his work and said he was the victim of racial bias. “I wasn’t trying to express that King was confrontational, but that he was thoughtful,” the Chinese sculptor told Cox Newspapers. “I just want to focus on King’s ideals. … We shouldn’t look at the color of someone’s skin.”

Mr. Lei also defended Mao. “He isn’t as bad as some people think,” the artist told Cox, while acknowledging that the man who led China from 1949 to 1976 “had made some mistakes.”

Mr. Young said it would have been preferable for the memorial to be made by a black American, but that if an American of another race had been selected, there “would be no controversy.”