The following is the latest of what we know about the derailment of the crash of Amtrak Train 89 en route from New York to Savannah, Ga.

• Amtrak Northeast Corridor service and SEPTA Wilmington/Newark Line service have resumed through the area in Chester, Delaware County, where an Amtrak train slammed into a railroad backhoe Sunday morning, killing the two workers on the maintenance vehicle and injuring 37 passengers on the train. Delays, however, should be expected.

• The two workers have not been identified yet. Autopsies are slated for today.

• NTSB investigators have recovered the trains data event recorded devices and its forward and inward facing cameras. They are looking into the crash being caused by human error, mechanical failure, a dispatching mistake or any combination of the three. It is not known yet how fast the train was going, but the posted speed is 110 mph in the area.

• Amtrak Train 89 was southbound on a trip from New York to Savannah, Ga., with 341 passengers and seven crew on board, when the collision occurred about 7:50 a.m. Sunday, derailing the two engines of the train.

• It was the second deadly Amtrak crash in the Philadelphia in less than a year, following the May 12 derailment of a northbound train on a curve at the Frankford Junction that killed eight and injured hundreds.