A bomb exploded in Iraq's capital city on Thursday, killing at least 45 people.It happened on a street filled with car dealerships and garages in southern Baghdad, according to Reuters. Islamic State militants claimed responsibility in a statement released on social media that said the group was targeting Shiites Muslims."This attack was on a large scale, but many similar, small bombings happen every day in the Iraqi capital, a constant bloody reminder that although ISIS no longer holds a third of Iraq's territory, the extremists and their allies are still powerful and ruthless," NPR's Alice Fordham reports from Irbil, Iraq."This bombing comes as Iraq's security forces gear up to begin an assault on ISIS in the west side of the northern city of Mosul," Alice adds. "Aid agencies say hundreds of thousands of people are living under ISIS control there, and have raised fears for their safety."Photos from the scene showed numerous burned-out cars and twisted metal.It's the second time this week an explosion has hit car markets, Reuters reports, "suggesting the group has found it easier to leave vehicles laden with explosives in places where hundreds of other vehicles are parked."U.S. State Department acting spokesman Mark Toner condemned the "horrible terrorist attack." He added that "these acts of mass murder are yet another example of ISIS's utter contempt for human life and its efforts to sow discord and division among the Iraqi people." Copyright 2017 NPR. To see more, visit http://www.npr.org/.