3 PM ET: Firefighter killed in building collapse, Naomi Osaka drops Wimbledon, Snapchat goes premium & more

A firefighter has died after a building collapse in Philadelphia. A man in California attacks three people in San Francisco’s airport. Meanwhile, TSA sees the highest influx of passengers since Thanksgiving.  Naomi Osaka withdraws from Wimbledon - we’ll explain why. Lastly, Snapchat might soon offer users a premium version of their app.  To learn more about how CNN protects listener privacy, visit cnn.com/privacy