What We're Following This Afternoon

Seeking a motive: “We don’t know why they did it,” President Obama said of the couple who killed 14 people and wounded 17 others in San Bernardino, California. Investigators are looking at terrorism and workplace grievance as possible motives, he said. Police identified the shooters as Rizwan Farook, 28, and his wife, Tashfeen Malik, 27. Both were killed after Wednesday’s shooting.

Opening military combat jobs to women: Defense Secretary Ash Carter ordered the armed services to open all combat jobs to women. “Our force of the future must continue to benefit from the best people America has to offer," Carter said. “In the 21st century, that requires drawing strength from the broadest possible pool of talent. This includes women, because they make up over 50 percent of the American population.” Update: More here

A guilty verdict: Former Massey Energy CEO Don Blankenship has been found guilty of conspiring to violate federal mine-safety standards and defrauding the Mine Safety and Health Administration. The charges related to the April 2010 explosion at the Upper Big Branch mine in West Virginia that killed 29 mine workers. Blankenship was found not guilty on two other charges of making false statements to the public and the SEC. Update: More here

Our headlines from the morning are here.