Seven people were killed when a military post was attacked near a rally held a day ago in Tehran to protest the re-election of President Mahmoud Ahmadinejad, radio Payam announced. According to the British Guardian newspaper, 12 people were killed.
Local sources reported that at least 17 more people were killed in several incidents in Tehran and other Iranian cities over the past two days.
"Several thugs wanted to attack a military post and vandalize public property in the vicinity of Azadi Square," the radio said referring to the site of the rally held on Monday.
"Unfortunately seven people were killed and several others wounded in the incident."
The report Tuesday gave no details. It was the first official confirmation of the shooting in Tehran's Azadi Square. Witnesses there saw at least one person shot dead and several others seriously wounded after shooting from a compound for volunteer militia linked to Iran's powerful Revolutionary Guard.
The office of leading Iranian reformist Mohammad Ali Abtahi said he was arrested on Tuesday. Abtahi, a former vice president who backed a pro-reform candidate in last Friday's disputed presidential election, was arrested in the morning, it said without giving further details.
Tehran clashes (Photo: AP)
Iran's Parliament Speaker Ali Larijani blamed the interior minister for attacks on civilians and university students in Tehran, local news agency ILNA reported.
"What does it mean to attack university students in the middle of the night in their dormitory and a civilian residential complex," Larijani told parliament. "The interior minister is responsible in this regard and he should respond," he said.
Russia: Elections an internal affair
Ahmadinejad arrived in Russia on Tuesday to attend a regional security summit.
The Iranian president had been expected to arrive Monday and meet with Russian President Dmitry Medvedev on the sidelines of the summit of the Shanghai Cooperation Organization.
He postponed the trip for one day amid street protests in Iran following his re-election in a bitterly disputed vote. No reason was given for the postponement.
Russia welcomed Ahmadinejad to Moscow and said the disputed election was a domestic matter.
"The Iranian elections are the internal affair of Iran," Deputy Foreign Minister Sergei Ryabkov told reporters in the Urals city of Yekaterinburg.
"We welcome the fact that elections took place, we welcome the new president on Russian soil and see it as symbolic that he made his first visit to Russia. This allows hope for progress in bilateral relations," Ryabkov said.
Ahmadinejad attended Tuesday's session of the regional security summit in the Ural Mountains city of Yekaterinburg.
Iran is an observer to the Shanghai Cooperation Organization, which is dominated by Russia and China and includes Kazakhstan, Kyrgyzstan, Tajikistan and Uzbekistan.
Dudi Cohen, AFP, The Associated Press and Reuters contributed to this report