Burials at Behesht-e Zahra cemetery were disrupted by police last month
A member of a parliamentary committee reportedly says it is investigating claims of a mass burial of protesters after Iran's disputed June election.
Last week, a reformist website said "tens" of people had been interred in anonymous graves at a Tehran cemetery.
"Parliament is investigating a rumour about a mass burial of post-vote detainees," Hamidreza Katouzian told the official Irna news agency.
At least 30 people died in clashes with security forces after the election.
The largest mass opposition demonstrations in Iran since the 1979 Islamic Revolution were sparked by allegations of widespread fraud in the presidential election, which saw the incumbent Mahmoud Ahmadinejad declared the winner by a landslide.
Earlier this month, one of the defeated opposition candidates, Mehdi Karroubi, called for an investigation into allegations that protesters had been raped in prison, and some even beaten to death. Officials have strenuously denied both accusations.
'Pictures and videos'
In a report published last week, Norooz - the news website of the opposition Islamic Iran Participation Front - said that "tens of unnamed and unknown people" had been buried in the Behesht-e Zahra cemetery in Tehran last month.
It said 28 burial permissions had been issued without names about a month after the election, in July, for section 302 of the cemetery, followed by another 16 three days later.
Mr Katouzian initially reacted to the allegation on Sunday by saying: "If anyone has any evidence, they can submit it to the Majlis [parliament]."
"There are a lot of rumours these days. Everyone can set up a website and post such reports on their websites," he said. "We cannot start an investigation based on rumours and speculation."
But on Tuesday, the Tehran MP said his parliamentary committee was now looking into the alleged mass burials and had contacted "relevant officials", who would provide a thorough report on the issue.
"We cannot confirm or deny the case at the current time and if it is needed we will visit Behesht-e Zahra," Irna quoted him as saying.
On Monday, the cemetery's manager reportedly said talk of a mass burial was "rumours".
Mahmoud Rezaiyan told AFP news agency: "In recent days we have not received any unidentified body and we were not forced to issue burial permits either. The report that there are mass graves is not true."
Norooz insists its report is correct and promised on Sunday to release "pictures and videos" of the anonymous graves within days.
The website also said the "people of Tehran can go and visit the graves, which are in the newer parts of the cemetery".