Updated post at 8:21 a.m.
Brian Leary, a U.S. Secret Service spokesman, said the vehicle has been cleared.
D.C. police said all lanes in the area are open.
Updated post at 8:16 a.m.
A U.S. Secret Service spokesman said 17th Street NW between Pennsylvania Avenue and H Street is closed because of a suspicious vehicle.
The spokesman, Brian Leary, said a K-9 dog indicated there was something in the vehicle.
Original post at 8:07 a.m.
D.C. police closed a section of Pennsylvania Avenue NW on Thursday morning while the U.S. Secret Service investigates a suspicious package.
Authorities shut down Pennsylvania Avenue NW from 17th Street NW to 18th Street NW. The closure began around 7:34 a.m. and continued as of 7:55 a.m.
No further details were available, police said.