NBC network reported that in the days leading up to the US attack on Iran, Tehran threatened - in a message personally delivered to President Donald Trump - that in retaliation it would activate dormant terror cells inside the United States. Two American officials and another source familiar with the details told the network that the message was conveyed to Trump through some mediator during the G7 summit held last week in Canada - a summit that Trump left earlier than planned to conduct consultations regarding the war with Iran.