Amtrak says rail service between New York and Philadelphia will not be up and running again until Tuesday.
Tracks and other equipment still need to be repaired after last week's train derailment in Philadelphia that killed eight people and left more than 200 injured.
Modified Amtrak service between Washington and Philadelphia will continue through Monday and New Jersey Transit is honoring Amtrak tickets between New York City and Trenton.
On Friday, investigators asked the FBI to look at whether a projectile, like a rock or bullet, hit Amtrak Regional 188 moments before it sped up and derailed at a curve in Philadelphia Tuesday night..
The latest information comes after NTSB investigators interviewed three Amtrak employees — including 32-year-old engineer Brandon Bostian.
Bostian remembers ringing the train's bell as it passed through North Philadelphia station, about 4 miles from the crash site, but his memory is blank after that point, NTSB's Robert Sumwalt said. The interview lasted an hour and a half and Bostian, accompanied by his lawyer, was described as "extremely cooperative."