An IG report on the anti-ISIS mission cited reports that the militias, known as the PMF, had obtained nine of the tanks.
The Iranian people "aren't buying" the regime's act, Defense Secretary Jim Mattis said.
The U.N. Security Council is planning an emergency meeting about Iran on Friday.
The Russian Armed Forces has unveiled its latest cutting-edge weapon in a New Year greetings video: cuddly puppies.
The protesters were killed in the town of Izeh, where people were demonstrating over the country's economic problems.
Protests were fanned in part by messages sent on the Telegram messaging app, which authorities blocked Sunday.
Early on Saturday, President Donald Trump tweeted out his support for the protests.
The Obama administration gave a free pass to Hezbollah's drug-trafficking and money-laundering operations to secure the deal.
Haley used the charred remnants of an Iranian missile as a backdrop to call for action against Tehran's "malign influence."
As Iraq emerges from three years of war with ISIS, the U.S. is looking to roll back the influence of neighboring Iran.