WASHINGTON — An examination of the cellphone used by the engineer on the Amtrak train that derailed in Philadelphia last month, killing eight people, turned up no evidence that he was on the phone at the time of the accident, federal investigators said Wednesday.

“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 National Transportation Safety Board said in an update of its investigation into the accident.

Investigators said an examination of Amtrak’s records also confirmed that the engineer had not used the train’s Wi-Fi system while he was operating the locomotive.

Still, at a Senate hearing on the derailment on Wednesday, T. Bella Dinh-Zarr, the vice chairwoman of the safety board, said the agency was continuing to examine more than 400,000 files of metadata on the phone.