The National Transportation Safety Board says a train that derailed in New York City was traveling 82 mph as it approached 30 mph zone.

The Metro-North Railroad commuter train jumped the tracks Sunday morning along a sharp curve where the speed limit drops from 70 mph to 30 mph. Four passengers died.

National Transportation Safety Board investigators on Monday mined the train’s data recorders, shedding light on such things as the train’s speed and the use of its brakes. It says it’s not aware of any problem with the train’s brakes.

The investigators have also sought to question the engineer and conductor for clues. The rail employees union says engineer William Rockefeller was injured in the wreck and is cooperating with investigators.

(AP)