Iranian President Mahmoud Ahmadinejad said Monday that Israel has "hired mercenaries to assassinate me." By Wednesday, several news sources including Reuters (citing confirmation from Ahmadinejad's office) were reporting that his motorcade was attacked in the city of Hamedan with some sort of grenade. Iran's state news media said later that day that the "grenade" was just a "firecracker" thrown by an overexcited youth — but not everyone is buying the official story. Did someone try to kill Iran's president? And if so, why deny it? (Watch a Russia Today report about the assassination rumors)

Iran is covering up an attack: It's "clear something made those around the Iranian president flinch," says Mark Philips at CBS News, and it's suspicious how quickly the grenade reports were "re-written by Iran's official state media." The most likely explanation is that Ahmadinejad is downplaying a serious attack because instead of coming from Israel, it's a sign of "internal enemies."
"Ahmadinejad: Underplaying threats on his life?"

Iran's state media is right (for once): Hard to believe, but I'm buying "the official line out of Iran," says Joe Weisenthal in Business Insider. It's "implausible" that somebody lobbed a grenade in a crowd and nobody died, and "unless you think that hand grenades thrown at presidents is an everyday occurrence in Iran," Hamadan would've instantly gone on "lock down." Instead, Ahmadinejad gave a big speech in a soccer stadium.
"Ahmadinejad was obviously not subject to an assassination attempt"

Even a firecracker could be an attack: Iran is, somewhat plausibly, blaming an "error in translation" for the grenade story that "raced around the world," say Peter Beaumont and Saeed Kamali Dehghan in The Guardian. The same word, narenjaks, is used for large, popular cherry bombs and grenades. That said, these firecrackers "can cause death and serious injuries," and "their use during a presidential visit" would merit "security concerns."
"Tehran denies reports of bomb attack on Mahmoud Ahmadinejad"