Iranian media report that two men have been executed, one of whom was put on trial following post-election unrest last year. But human-rights groups and the man's lawyer say he was in prison before the protests began.
State media announced the executions of the two men early Thursday.
The two are identified as Mohammad Reza Ali-Zamani and Arash Rahmanipour.
The semi-official ISNA news service and pro-government sources linked the men with nine others sentenced to death in connection with the unrest that followed the disputed re-election of President Mahmoud Ahmadinejad last year.
Zamani was seen in the mass trials of people charged in the protests.
But state-run Press TV said Zamani and Rahmanipour were executed in connection with a 2008 bombing blamed on a small monarchist group. Last year Press TV showed the men saying they had met with U.S and Israeli agents in connection to a bombing campaign.
Human-rights groups say it was a forced confession. As for the ties to post-election unrest, the groups say Zamani was in custody before the vote.
Further adding to the contradictions, Iran's Arabic station al-Alam reports the two were put to death for taking part in protests in December, two months after they were shown at the televised trials.
Some observers say the attempt to link diverse groups of government opponents together, and to hand down and carry out death sentences against them, helps the state shape public opinion.
Professor Amal Hamada follows Iranian politics at Cairo University.
"For an average Iranian guy who would read the news or follow the television reports about the opposition and seeing them all part of a great betrayal of the system and of the revolution, he will not be able to tell the differences between the secular opposition, or the religious opposition," he said.
Members of the Green Movement that sprang up to challenge the results of last year's presidential election are said to be preparing more protests to coincide with the February 11th anniversary of the 1979 Islamic revolution.
The government has warned it will not tolerate disruption of its planned events.