from jersey journal:

Smoke on the tracks at the Grove Street Path Station in Jersey City caused all train lines to briefly shut down early this morning, a Port Authority spokeswoman said.

Passengers were unloaded from a train at Grove Street at 12:15 a.m., the spokeswoman said.

Then lines were shut down for 15 to 20 minutes while the smoke was cleared and the train was taken to the Journal Square Station to make sure it was working properly, the spokeswoman said.

The smoke was caused by debris that rubbed up against the tracks as a train went by, she said.

As a result of the shutdown, PATH schedule was disrupted for several hours, she said.

Yea i saw alot of people rushing out of the station. Someone said there was an explosion and smoke and fire and everyone started running. Turns out it was a gas leak or something and all those fire engines and police left as quick as they got there.

I live near the Grove Path entrance, a LOT of sirens were going on for at least 30 minutes. It's quiet now, hope everyone is ok. The sirens got mad ass crazy for a while. I heard a lot of yelling beforehand.

Something popped at Grove. Then there was smoke and people running. Firetrucks heading there now.