COLLEGE PARK – (WAOK/AJC) -  South Fulton police say a good samaritan who tried to help a man,  whose van had tumbled down an embankment Tuesday afternoon,  has died after his legs were severed by a train,  while helping the injured unidentifed driver.  Neither man’s name has been released in connection with the accident.   Investigators say the minivan driver,  somehow lost control of his car,  and then rolled down an embankment off of Roosevelt Highway,  landing next to the CSX railroad tracks.  They say the good samaritan tried to assist the injured  man but he fell on the tracks,  and was hit by a passing train.    Police are still investigating the crash,  trying to piece together how the minivan driver left the roadway.