Amtrak's CEO is apologizing for the train derailment that killed eight people this week in Philadelphia.

FOX News Radio's Tonya J. Powers has more:

AMTRAK DERAILMENT ACCIDENT Amtrak President Joseph Boardman says the company takes full responsibility for the accident, and is cooperating in the investigation. 

The focus is now on the engineer of the train. Police want to see engineer Brandon Bostian's cell phone records.

NTSB investigators say in the last minute or so before the derailment, the train sped up from 70 miles per hour to more than 100 -- in a spot where the speed limit is 50.

NTSB Board Director Robert Sumwalt says it's not clear if Bostian manually increased that speed.

(Sumwalt) "He has agreed to be interviewed by the NTSB. We will be meeting with him in the next few days."

Amtrak hopes to have service again in that area by Monday.

Tonya J. Powers, FOX News Radio.