By AMY BETH HANSON, MARTHA BELLISLE and DAVID KOENIG
JOPLIN, Mont. (AP) — An Amtrak train that derailed in rural Montana over the weekend was going just under the speed limit at about 75 mph when it went off the track along a gradual curve. U.S. investigators also said Monday that the accident may have ejected some passengers. Three people died. Investigators from the National Transportation Safety Board are studying video from the train and another locomotive that went over the same track a little over an hour earlier. The train derailed before a switch in the line, where one set of tracks turned into two. That stretch of track had been inspected just two days before.