An Acela Express Amtrak train on its way from Boston to Washington, D.C., had a minor derailment Friday morning at New York’s Penn Station, railroad officials said.

Train 2151 left Boston at 5:05 a.m. As it was departing Penn Station at around 9 a.m. at a “slow speed,’’ it made contact with an incoming NJ Transit train, Amtrak spokesman Mike Tolbert said in an e-mail.

“The rear of the Acela train was still on the platform, and all 248 passengers have exited the train onto the platform and into the station safely,’’ Tolbert said.

One NJ Transit passenger, Jordan Geary, tweeted a photo of the damage. “My . . . train just collided with another oncoming train. Blew my window out and into me. Thankfully everyone is okay,’’ he tweeted.

Geary tweeted a few hours later that after the incident people had asked both loved ones and strangers, “Are you OK?’’

It was “beautiful to see,’’ he wrote.

Maddie Kilgannon can be reached at maddie.kilgannon@globe.com.