After combing through cell phone records, investigators from the National Transportation Safety Board found evidence indicating the engineer involved in May's Amtrak train derailment in Philadelphia did not use his phone at the time of the crash, according to a statement released Wednesday. Brandon Bostian, 32, was the engineer during the May 12 crash that killed eight people and injured more than 200.

"Analysis of the phone records does not indicate that any calls, texts or data usage occurred during the time the engineer was operating the train," the NTSB statement reads. "Amtrak’s records confirm that the engineer did not access the train’s Wi-Fi system while he was operating the locomotive."

The agency added that it's investigating whether the phone was in airplane mode or powered off. The statement also reported that Bostian voluntarily handed over the passcode to his phone.