Three things to know about the looming debt ceiling crisis
By Scott Horsley & Juliana Kim
Treasury secretary warns US could default on its debt as soon as June
By Tami Luhby & Nikki Carvajal
U.S. will hit its debt limit Thursday, start taking steps to avoid default, Yellen warns Congress
By Christina Wilkie, Kayla Tausche & Dan Mangan
Yellen warns of U.S. default risk by early June, urges debt limit hike
By David Lawder & Kanishka Singh