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Input: Security forces also have struck back with targeted arrests of pro-reform activists and blocks on text messaging and pro-Mousavi Web sites used to rally his supporters.
 A top Mousavi aide  Ali Reza Adeli  told The Associated Press that a rally planned for later Monday was delayed. Iran's Interior Ministry rejected a request from Mousavi to hold the rally and warned any defiance would be "illegal " state radio said.
 But one of Mousavi's Web sites still accessible in Iran said Mousavi and another candidate  Mahdi Karroubi  planned to walk through Tehran streets to appeal for calm. A third candidate  the conservative Mohsen Rezaei  has also alleged irregularities in the voting.
 State TV quoted Khamenei urging Mousavi to try to keep the violence from escalating and saying "it is necessary that activities are done with dignity."
 "I want to stay because they beat us and we won't retreat " he added.

Iran supreme leader orders probe of vote fraud