Thanks to DP, Abby, Bobby, Eric, iCan and Alex for sending photos. Developing. Updates as we learn more.
UPDATE: Dave Statter reports: “black smoke pouring from the vent on a roof in SW. Turns out to be GSA Building switching over to oil. DC Fire & EMS was dispatched quite a few blocks to the the west at the Trump Hotel in NW. All okay and units have cleared.”
From Helder Gil: “Source is the Feds’ heating plant HVAC system at 13 & C St SW”
From DC Fire and EMS: “#DCsBravest have received many inquiries about black smoke seen near downtown. The smoke is coming from boilers at the GSA heating plant in Southwest. There is no fire and no emergency.”