The engineer aboard an Amtrak passenger train reported seeing some ``misalignment in the rail'' shortly before a derailment that killed one passenger and injured dozens of others.

``He applied his brakes. Six seconds later, he reported seeing the right rail roll over in front of him,'' Mark Rosenker, vice chairman of the National Transportation Safety Board, said Thursday after interviews with the engineer.

The Amtrak train derailed Tuesday night over a swamp on a stretch of CN Railway-owned track with a rough history. Four freight trains, including one carrying toxic chemicals, derailed on that area since 1994.

Several passengers say the crew warned them minutes before the derailment that the section of track they were on was always a bumpy, choppy ride.

CN Railway spokesman Ian Thomson said the rails were inspected just two days before the wreck. He said two freight trains rode the same track that afternoon and engineers reported no problems.

Rosenker declined to release the names of the engineer or the conductor. Amtrak officials said both employees were veterans of the railroad.