While Western intelligence agencies have long thought that al Qaeda operatives are present on Iranian soil , they were thought to be under some form of house arrest and under strict control . Canadian authorities suspect al Qaeda elements in Iran provided guidance to alleged plotters . Iran has denied the alleged rail conspiracy could have been plotted from its territory . The U.S. and Israel are also investigating a possible Iranian role in an attack on Israeli athletes at the 1972 Munich Olympics that killed 11 Israelis. Al Qaeda 's interest in attacking railroads underscored following death of Osama bin Laden .
Canadian authorities suspect al Qaeda elements in Iran provided guidance to alleged plotters . Iran has denied the alleged rail conspiracy could have been plotted from its territory . The U.S. and Israel are also investigating a possible Iranian role in an attack on Israeli athletes at the 1972 Munich Olympics that killed 11 Israelis. Al Qaeda 's interest in attacking railroads underscored following death of Osama bin Laden .