A boy carries a portrait of Iranian Revolutionary Guard Gen. Qassem Soleimani, who was killed in the U.S. airstrike in Iraq, prior to the Friday prayers in Tehran, Iran, Jan. 3, 2020. Iran has vowed "harsh retaliation" for the U.S. airstrike near Baghdad's airport that killed Tehran's top general and the architect of its interventions across the Middle East, as tensions soared in the wake of the targeted killing. (AP Photo/Vahid Salemi)