Campaign offices of an Iranian presidential candidate were burned down on Monday night, as it was revealed that a former Iranian president narrowly escaped an assassination attempt last week in the run-up to the elections. One of the intended passengers for a domestic Iranian flight on which a bomb was found on Saturday was former Iranian president Mohammad Khatami, the Iranian daily Sarmayeh reported on Monday. A bomb was discovered on the plane 15 minutes into the flight from the southern Iranian city Ahvaz bound for the capital Teheran. The plane turned back to the airport in Ahwaz, where authorities disarmed the bomb. According to regional media, Khatami was scheduled to be on the flight, but his plans changed and he left on an earlier flight. It was unclear why he altered his schedule. Khatami is a reformist and has been campaigning for reformist candidate Mir Hossein Moussavi in the upcoming presidential elections slated to take place on June 12. The reports of the attempted assassination were revealed as Moussavi's campaign office in the city of Qum, in northwest Iran, was torched on Monday afternoon, the IRNA news agency reported. No group claimed responsibility for the attack. Moussavi, who was prime minister during the years 1981-1989, is considered to be the main challenger to President Mahmoud Ahmadinejad, who is running for a second term. He recently criticized Ahmadinejad's economic policies, claiming these policies had sent the country into economic chaos and undermined the nation's standing in the world. Ahmadinejad is also facing criticism from the Center for Strategic Research, which conducts research on behalf on the Iranian Foreign Ministry, for trying to rewrite the country's history by portraying himself as a "national nuclear hero," according to the official Iranian Press TV. Last Friday, Ahmadinejad's campaign offices in Zahedan, near the Pakistani border, were attacked by unidentified gunmen, wounding two adults and a child. Conflicting polls have shown Moussavi to be anywhere between four points ahead of Ahmadinejad or significantly trailing the incumbent president. The discrepancy between the surveys is believed to be due to the political interests behind those conducting the polls. Critics of Ahmadinejad are certain the government will cheat in the election and say the reformists will need to gain millions of votes over Ahmadinejad in order to secure a victory. The three opposition candidates - Moussavi, Mehdi Karroubi and Mohsen Rezaei - have turned to text messages, email, blogs and online social networking Web sites as platforms to reach out to young Iranians.