Lazare Kabaya Kobagaya, 84, was accused of directing members of his Hutu ethnic group to burn the homes of the rival Tutsi group in 1994 and participating in other attacks against them in which hundreds were killed.
He obtained U.S. citizenship in July 2006 in Kansas but a U.S. grand jury indicted him in 2009 for making false statements as part of his immigration application, including lying that he lived in Burundi from 1993 to 1995 and that he had not engaged in genocide.
He faced one count of immigration fraud and one count of visa fraud. He pleaded not guilty to the charges in April 2009.
After a five-week trial and three days of deliberations, a jury found him guilty on the visa fraud count, but was unable to reach a verdict on the other count. As a result of the deadlock, the judge declared a mistrial on the immigration fraud charge.
In its verdict, jurors determined Kobagaya was guilty only of lying about being in Burundi from 1993 to 1995, but not of lying about whether he participated in genocide, according to the Justice Department.
He was also accused in the indictment of attacking and threatening others who refused to participate in the killings.
The indictment alleged that in one instance, he ordered Hutus to kill Tutsi women who had previously been spared because they were married to or related to Hutu men. At least one woman was killed and others were attacked, the indictment said.
Kobagaya faces up to 10 years in prison for the visa fraud count and prosecutors could seek to a new trial on the other count. It was not immediately clear whether the United States could or would seek to deport him.
Officials have estimated 500,000 to 800,000 Rwandans were killed during the ethnic fighting and more than 2 million fled the country.