Iran's top legislative body Tuesday ruled out annulling a disputed presidential poll that has prompted the biggest street protests since the 1979 revolution but said it was prepared for a partial recount. In what appeared to be a first concession by authorities to the protest movement, the 12-man Guardian Council said it was ready to re-tally votes in the poll in which President Mahmoud Ahmadinejad was declared the runaway winner. But the powerful Council rejected reformist calls to annul Friday's election that set off swift-moving political turmoil, riveting attention on the world's fifth biggest oil exporter which is locked in a nuclear dispute with the West. Iran's English-language Press TV said seven people were killed and several wounded at the end of Monday's rally – a mainly peaceful gathering attended by many tens of thousands – when “thugs” tried to attack a military post in central Tehran. An Iranian photographer at the scene had said militiamen opened fire when people in the crowd attacked a post of the Basij religious militia. He said one person was killed and many wounded in the shooting. Supporters of Mirhossein Mousavi, outraged at his defeat in what they viewed as a stolen election, planned another rally Tuesday, even though seven people were killed on Monday on the fringes of a huge march through the streets of Tehran. Mousavi urged people not to attend the banned rally at Vali-ye Asr Square in Tehran “to protect lives” saying it was cancelled, but it was not clear if the call was heeded. Supporters posted defiant messages on Twitter, calling for the demonstration to go ahead and offering security updates. State television showed live pictures of what it said were Ahmadinejad supporters gathering at the Vali-ye Asr Square, showing thousands of people, some waving Iranian flags, possibly setting the scene for more confrontation. Iranian state television said Tuesday the “main agents” in post-election unrest had been arrested with explosives and guns. It gave no further details in a breaking news headline. Further protests, especially if they are maintained on the same scale, would be a direct challenge to the authorities who have kept a tight grip on dissent since the 1979 overthrow of the Shah.