A malfunctioning signal light may have caused yesterday's fatal train wreck outside of Los Angeles according to officials with the National Transportation Safety Board (NTSB). Although a spokesperson for the NTSB said it is still too early in the investigation to determine the exact cause of the accident, investigators have turned their attention to a railroad signal light that the Burlington Northern Santa Fe freight train passed shortly before it collided with the Metrolink commuter train.

NTSB Chairwoman Marion Blakey said the freight train "would have had a red signal at that point" if it had been functioning properly. Two people died and approximately 265 others were injured in the accident. Over 160 passengers were treated at ten Orange County hospitals. Eight commuters are currently listed in critical condition.