That’s what the Post reports.  I got a political email explaining more:

Here is a quick update on the race in the 11th Congressional District. Currently Keith Fimian sits 487 votes down in the total count. There are currently two machines in two different precincts in Fairfax County that malfuncioned.  They are sealed and are locked up in the Fairfax County Government Center.

Those machines will be broken open and counted at 8AM and once that process is completed and verified, we will then proceed to the 9AM canvass. Once the canvass is complete, and the count becomes official, we will then determine what the next steps are per a recount.