Iran's police chief Ahmad Radan said on Friday that officers had been authorized to shoot at suspected looters amid the war with Israel and the United States.
"Because we are in wartime conditions, I have issued orders to shoot at potential thieves," Radan told state TV, adding that any thieves would be "swiftly neutralized".
He also said that authorities had taken measures to maintain order online.
"We will not allow a group of paid agents to undermine the unity that the people achieved with the blood of thousands of martyrs by spreading agitation," said Radan.
War has spread across the Middle East since Saturday after the United States and Israel launched strikes on Iran which killed the Iranian republic's supreme leader Ali Khamenei.
Iran responded by attacking US bases in Gulf countries and Israel with drone and missile strikes.
Iran's health ministry said nearly 1,000 people had been killed in the US and Israeli strikes which hit military sites as well as residential areas and other infrastructure.
AFP could not independently verify the toll.
Iranian attacks killed at least 10 people in Israel according to first responders there, while the US military has reported the deaths of six of its personnel since the war began.
