The engineer of a New Jersey Transit train that slammed into Hoboken Station in September apparently suffered from undiagnosed sleep apnea.
Two officials told the Associated Press 48-year old Thomas Gallagher was diagnosed with the condition after the September 29 crash.
One of the officials says investigators are looking into whether or not the disorder is a potential cause of the incident.
A woman standing on the platform was killed and 100 others were hurt.
Investigators say the train was going twice the 10 mph speed limit when it entered the station.
Gallagher told investigators he had no memory of the crash and remembered waking up on the floor.
The National Transportation Safety Board said it wasn't able to confirm specifics about Gallagher's health.