I'm in the DC Metro area, about an hour out from Dupont Circle, at the Glenmont end of the Redline, past Glenmont Station on the side of the Metro where the accident happened. Too far away to drive in, and people are being asked not to visit the site, so I'm getting my information from Twitter and local news outlets.
From reports in The Washington Post, two trains collided, both apparently going in the same direction. I've heard confirmed reports that as many as 6 people died, including the female Metro driver of one of the trains. Seems that both trains were traveling in the same direction, on the same track, though the details haven't been released yet.
(Update, midnight: @NBCWashington: Metro Crash Latest: At least 9 dead, 70 injured / Expect major Red Line delays today, 8am news conference scheduled.)
The crash happened between the Fort Totten and Takoma Stations on the Redline, on the Silver Spring side of DC Metro's Redline.
Here's some information picked up on Twitter about the situation, with more in comments:
@MetroOpenDoors reports: DC Police requesting people DO NOT travel to the incident site. To find out about travelers call DC Police at 202-727-9099
@MetroOpenDoors reports: The only other time in Metrorail's 33-year history that there were customer fatalities was in January 1982
@MetroOpenDoors reports: Expect significant delays as the area of track involved in the accident will remain closed to train traffic through Tuesday.
@WashingtonPost reports: Witness to #DC Metro crash: Passengers Banged On Windows: http://tr.im/povr
@WashingtonPost reports: More updates on Get There blog about the DC Metro crash: http://tr.im/pofo #redline