Iran's Revolutionary Court sentenced an American to death for spying for the CIA, the semi-official Fars news agency reported Monday.
"Amir Mirza Hekmati was sentenced to death ... for cooperating with the hostile country (the United States) and spying for the CIA," Fars said, without giving a source.
"The court found him Corrupt on Earth and Mohareb (waging war on God)," it added.
The Obama administration denied Monday that Hekmati was a CIA spy, and sharply criticized the Islamic republic in Tehran for what it called a pattern of arresting innocent people for political reasons.
White House spokesman Tommy Vietor said officials were still trying to learn the details of the sentence against Hekmati. If true, the U.S. would condemn the verdict, he said.
The human rights group Amnesty International said Hekmati didn't receive a fair trial, and called on Iran to set aside the death sentence.
Last week, Hekmati's family said he was not getting adequate legal representation.
In a statement, they said that his "only advocate in Iran is a government-appointed lawyer who he first met on the day of his trial."
"We have struggled to provide Amir with an attorney in Iran," the family wrote in the statement. "We have sought to hire at least 10 different attorneys in Tehran to no avail."
The Fars report Monday did not say when the verdict was issued. Under Iranian law, he has 20 days to appeal.
Hekmati's family said the former U.S. military translator was visiting his grandmothers.
Hekmati, 28, was born in Arizona and graduated from a Michigan high school. His father Ali is a professor at a community college in Flint, Michigan.
The State Department has called for Hekmati's release, and spokesman Victoria Nuland told reporters in Washington last week that the department continues to wait for Iranian authorities to grant Swiss diplomats access to him in prison.
The Swiss government represents U.S. interests in Iran because the two countries don't have diplomatic relations.
Nuland said Hekmati is a dual U.S.-Iranian national, and "the Iranian government has historically not recognized our rights to access."
"That doesn't change the fact that we will keep asking for it," she said.
Iran charges that as a U.S. Marine, Hekmati received special training and served at U.S. military bases in Iraq and Afghanistan before heading to Iran for his alleged intelligence mission.
Last month, Fars reported that the prosecution had applied for capital punishment because the suspect "admitted that he received training in the United States and planned to imply that Iran was involved in terrorist activities in foreign countries" after returning to the U.S.
That report said Hekmati repeated a confession broadcast on state TV Dec. 18.
Hekmati's lawyer, who was identified only by his surname, Samadi, denied the charges, according to the December report.
In court on Dec. 27, Hekmati was quoted by Fars as saying, "I was deceived by the CIA."
"Although I was appointed to break into Iran's intelligence systems and act as a new source for the CIA, I had no intention of undermining the country," Fars quoted Hekmati as saying.
Current and former U.S. government officials told Reuters in November that Iran had succeeded in uncovering the identities of several CIA informants.