The engineer of the commuter train that crashed in Hoboken in September had undiagnosed sleep apnea, officials said.

The train accelerated, derailed and hit a wall at the Hoboken station at 21 mph — more than double the speed limit — killing one woman and injuring dozens of people. The crash occurred during morning rush hour on Sept. 29.

RELATED: NJ Transit train crashed at twice the speed limit in Hoboken: NTSB

Two anonymous officials who were briefed on the investigation told The Associated Press that 48-year-old Thomas Gallagher, the engineer, was diagnosed with sleep apnea after the crash.

The National Transportation Safety Board has not confirmed the information, according to the report.

Gallagher told investigators that his only memory of the crash was waking up on the floor.