An Iranian military court sentenced two people to death on Wednesday for the murder of three protesters taken into custody after last June's contested presidential election, the official IRNA news agency reported.
IRNA said the jailed protesters had died as a result "intentional assault and battery", but gave no further details of the circumstances of their deaths and did not identify the people convicted of killing them.
The protesters who died in custody have been considered martyrs by the opposition. Authorities had initially said they died of meningitis, but a coroner said they died as a result of beatings.
If those sentenced for the killings are police or prison guards it would be the first time such officials have been convicted for abusing post-election protesters.
A further nine people were ordered to pay fines and blood money and receive lashes for the abuse of prisoners at the Kahrizak detention center, south of Tehran. One person was cleared. The convictions are subject to appeal.
Thousands of people were arrested after the reelection of hardline President Mahmoud Ahmadinejad. Most have been freed, though dozens, including former senior officials, have been jailed for up to 16 years and at least two have been hanged.
Scores of people have filed complaints of their mistreatment at Kahrizak and police confirmed in August that serious violations had taken place there.
The government, which faced down widespread street unrest after the election, accused foreign enemies of fomenting "sedition". It is likely to hold up Wednesday's convictions as evidence it does not tolerate human rights abuse.
Amnesty International has said Iran uses torture, politically-motivated executions and the imprisonment of journalists, students, activists and clerics to stifle dissent.
A parliamentary report in January said more than 145 detainees were kept for several days in a room of 70 square metres at Kahrizak, which was closed in July on the orders of Supreme Leader Ayatollah Ali Khamenei.
In a separate case, state TV reported that 33 people had been referred to court in connection with attacks on a Tehran University dormitory and a residential apartment complex during the post-election unrest.
Opposition activists said four students -- three men and one woman -- were killed during the violence which they said was carried out by Islamic militia and police. The university chancellor denied anyone was killed.