Live blog: Running updates on Amtrak, Burundi and DeflateGate

(CNN)In Philadelphia, officials and investigators are still scrambling to determine exactly how an Amtrak commuter train derailed, killing seven. In Burundi, yesterday's report that a coup was under way is now being brushed off by the president as a "joke." And in the NFL, New England Patriots star quarterback Tom Brady has until 5 p.m. ET to appeal his DeflateGate suspension.

Stay tuned to our live blog as we bring you the latest updates on three of today's biggest stories.