COLUMBIA, S.C. (AP) — Federal investigators are taking testimony about a deadly collision between a passenger train and a freight train in South Carolina this year.

The National Transportation Safety Board is holding the hearing Tuesday in Washington to discuss the Feb. 4 crash near Cayce. Officials from CSX, Amtrak and the Federal Railroad Administration are giving testimony.

The NTSB has said a switch was in the wrong position, sending an Amtrak passenger train onto a side track where a CSX freight train was parked. The Amtrak engineer and conductor died. More than 100 passengers were taken to hospitals.

Investigators have said human decision-making "likely" played a key role, but the agency hasn't released its final report.