After a deadly derailment in Philadelphia, service on the Northeast Corridor will be partially restored Monday and fully restored by Tuesday, Amtrak officials said Thursday.

Commuters have been using alternative means of transportation and modified routes since the derailment, which killed eight people.

As the crash investigation continues, there is no Amtrak service through Philadelphia this week. New Jersey Transit is cross-honoring Amtrak tickets between Trenton and New York.

Transit officials say once commuters arrive at the Trenton Transit Center, they can walk outside to the north bus stop. There, they will find a bus marked "shuttle." The shuttle bus will take commuters to the West Trenton Station where they can find a direct route to Philadelphia.

The service changes have left many commuters who travel between New Jersey and Philadelphia confused. One woman said she wasn't able to go to work Wednesday, but she is determined to get there. "I'm going to try it," she said. "I've never done it."

The free shuttle departs every 20 minutes.

New Jersey Transit will honor Amtrak tickets between New York City and Trenton. Commuters will have to show Amtrak or Septa tickets.

There is also modified service between Washington and Philly and Manhattan and Boston. And Septa service is suspended between Trenton and Philadelphia.

Passengers can check schedules online or by calling 800-USA-RAIL.