Investigators today announced that the Metrolink commuter train involved in a crash with a freight train yesterday in Rialto ran past a red signal. "But we don't know why," Ted Turpin of the National Transportation Safety Board told the LA Times. A red stoplight was ran by the Metrolink train that crashed head on with a freight train in September killing 25 in Chatsworth. Yesterday's crash was minor in comparison--five people were injured--but it is raising questions about Metrolink's ability to safely operate trains on tracks shared by other train agencies.