Anyone Else Experience This?

From an anonymous reader:

I want to report what I suspect was a small explosion on an Orange Line Metro train this afternoon. About an hour ago (4:30 p.m.), I was riding on a Vienna-bound Orange Line train that was stopped at the Ballston station.

The doors closed, and the train had barely begun to move when a very loud bang was heard that shook the train.

I didn't see anything, but other passengers in my car mentioned seeing a flash of light.

The train operator could be heard over the call box asking if anyone was injured.

I suppose the answer was no, because we proceeded to East Falls Church, and eventually to Vienna, where the train was taken out of service.

The operator did not make any announcements, but was heard at East Falls Church asking for passengers in car 1202 (I was in 1208) to page him on the emergency call box.