New Jersey Transit posted this alert three minutes ago:

Due to Portal Bridge problems, service is temporarily suspended in and out of PSNY. NEC and NJC service in/out of Newark Penn is subject to 60 minute delays. Cross honoring with PATH and NJT Bus.

The Amtrak Portal Bridge crosses the Hackensack River.

PSNY = PennStation New York.
NEC= Northeast Corridor
NJC = North Jersey Coast line